Warnings for closed output stream in logs

[rabidllama]

Here's what I did

Built a container and made requests whilst using production level logging. All requests made result in a lengthy output to the logs.

---

Here's what I got

Warnings are being logged as apparently the response stream has already been closed. This does not show in debug level debugging as the springframework loglevel there is set to error, whereas in the production it is set to warning (so production actually logs more than the debug?)

12 Apr 12:20:33 WARN [annotation.ExceptionHandlerExceptionResolver] - Failure in @ExceptionHandler org.heigit.ors.api.controllers.RoutingAPI#handleReadingBodyException(Exception)
java.io.IOException: Cannot write to a closed output stream
	at org.heigit.ors.servlet.filters.GZIPResponseStream.write(GZIPResponseStream.java:86) ~[classes/:6.4.1]
	at sun.nio.cs.StreamEncoder.writeBytes(StreamEncoder.java:233) ~[?:?]
	at sun.nio.cs.StreamEncoder.implFlushBuffer(StreamEncoder.java:312) ~[?:?]
	at sun.nio.cs.StreamEncoder.implFlush(StreamEncoder.java:316) ~[?:?]
	at sun.nio.cs.StreamEncoder.flush(StreamEncoder.java:153) ~[?:?]
	at java.io.OutputStreamWriter.flush(OutputStreamWriter.java:254) ~[?:?]
	at org.springframework.util.StreamUtils.copy(StreamUtils.java:148) ~[spring-core-5.2.10.RELEASE.jar:5.2.10.RELEASE]

---

Here's what I was expecting

That there are no warnings produced from Spring when making requests

---

Here's what I think could be improved

Investigate why the corresponding stream is being closed before it should be, or why it is being used in the first place.