Apache Flink

Good morning all! I'm having some trouble with setting a parameter at runtime to use for configuring the StatsD metric reporter.
Running in Kubernetes, I'm trying to use an environment variable to define the host for the statsD client with this in my `flink-conf.yaml`:
```env.java.opts: -Dmetrics.reporter.stsd.host=${DD_AGENT_HOST}```
However, at startup, the reporter crashes with:
```2023-03-24 12:13:55,011 ERROR org.apache.flink.runtime.metrics.ReporterSetup               [] - Could not instantiate metrics reporter stsd. Metrics might not be exposed/reported.
java.lang.IllegalArgumentException: Invalid host/port configuration. Host: null Port: 1125
	at org.apache.flink.metrics.statsd.StatsDReporter.open(StatsDReporter.java:72) ~[?:?]
...```
... so it seems the `metrics.reporter.stsd.host` is not being used in the dynamic properties...
_Should_ it be possible to set metric reporter properties using the `env.java.opts` ?

Thanks you for any pointers!

I also tried setting the value manually to confirm it's not something with the shell variable expansion, like:
```env.java.opts: -Dmetrics.reporter.stsd.host=10.x.x.x```
And received the same exception