Hi guys, I have stumbled upon the following issue while trying to build Druid from source:

WARN [main] org.apache.druid.java.util.common.RetryUtils - Retrying (8 of 9) in 73,316ms.
org.skife.jdbi.v2.exceptions.UnableToObtainConnectionException: java.sql.SQLException: Cannot create PoolableConnectionFactory (Unknown system variable 'transaction_isolation')
at org.skife.jdbi.v2.DBI.open(DBI.java:230) ~[jdbi-2.63.1.jar:2.63.1]
at org.skife.jdbi.v2.DBI.withHandle(DBI.java:279) ~[jdbi-2.63.1.jar:2.63.1]
at org.apache.druid.metadata.SQLMetadataConnector.lambda$retryWithHandle$0(SQLMetadataConnector.java:142) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.java.util.common.RetryUtils.retry(RetryUtils.java:129) ~[druid-core-25.0.0.jar:25.0.0]
at org.apache.druid.java.util.common.RetryUtils.retry(RetryUtils.java:81) ~[druid-core-25.0.0.jar:25.0.0]
at org.apache.druid.java.util.common.RetryUtils.retry(RetryUtils.java:163) ~[druid-core-25.0.0.jar:25.0.0]
at org.apache.druid.java.util.common.RetryUtils.retry(RetryUtils.java:153) ~[druid-core-25.0.0.jar:25.0.0]
at org.apache.druid.metadata.SQLMetadataConnector.retryWithHandle(SQLMetadataConnector.java:142) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.metadata.SQLMetadataConnector.retryWithHandle(SQLMetadataConnector.java:152) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.metadata.SQLMetadataConnector.createTable(SQLMetadataConnector.java:189) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.metadata.SQLMetadataConnector.createPendingSegmentsTable(SQLMetadataConnector.java:217) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.metadata.SQLMetadataConnector.createPendingSegmentsTable(SQLMetadataConnector.java:603) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.druid.cli.CreateTables.run(CreateTables.java:125) ~[druid-services-25.0.0.jar:25.0.0]
at org.apache.druid.cli.Main.main(Main.java:112) ~[druid-services-25.0.0.jar:25.0.0]
Caused by: java.sql.SQLException: Cannot create PoolableConnectionFactory (Unknown system variable 'transaction_isolation')
at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2152) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:1903) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1413) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.skife.jdbi.v2.DataSourceConnectionFactory.openConnection(DataSourceConnectionFactory.java:36) ~[jdbi-2.63.1.jar:2.63.1]
at org.skife.jdbi.v2.DBI.open(DBI.java:212) ~[jdbi-2.63.1.jar:2.63.1]
... 13 more
Caused by: java.sql.SQLException: Unknown system variable 'transaction_isolation'
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3933) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3869) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2524) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2675) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2465) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2439) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1365) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.loadServerVariables(ConnectionImpl.java:3767) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3196) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2233) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2015) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:768) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at jdk.internal.reflect.GeneratedConstructorAccessor37.newInstance(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:?]
at java.lang.reflect.Constructor.newInstance(Constructor.java:490) ~[?:?]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:403) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:385) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:323) ~[mysql-connector-java-5.1.49.jar:5.1.49]
at org.apache.druid.metadata.BasicDataSourceExt.lambda$createConnectionFactory$0(BasicDataSourceExt.java:185) ~[druid-server-25.0.0.jar:25.0.0]
at org.apache.commons.dbcp2.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:205) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.validateConnectionFactory(BasicDataSource.java:2162) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2148) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:1903) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1413) ~[commons-dbcp2-2.0.1.jar:2.0.1]
at org.skife.jdbi.v2.DataSourceConnectionFactory.openConnection(DataSourceConnectionFactory.java:36) ~[jdbi-2.63.1.jar:2.63.1]
at org.skife.jdbi.v2.DBI.open(DBI.java:212) ~[jdbi-2.63.1.jar:2.63.1]
... 13 more