integration tests for groovy script session

[devinrsmith]

We don't test groovy script session execution in CI.

Recently, due to the removal of large swaths of code, it has been breaking with errors like:

grpc-api_1    | Script_1: 29: unable to resolve class com.illumon.iris.gui.widget.poliform.VariableTypeForm
grpc-api_1    |  @ line 29, column 1.
grpc-api_1    |    import static com.illumon.iris.gui.widget.poliform.VariableTypeForm.*;
grpc-api_1    |    ^
grpc-api_1    | 
grpc-api_1    | Script_1: 29: unable to resolve class com.illumon.iris.gui.widget.poliform.VariableTypeForm
grpc-api_1    |  @ line 29, column 1.
grpc-api_1    |    import static com.illumon.iris.gui.widget.poliform.VariableTypeForm.*;
grpc-api_1    |    ^
grpc-api_1    | 
grpc-api_1    | 2 errors
grpc-api_1    | 
grpc-api_1    |         at org.codehaus.groovy.control.ErrorCollector.failIfErrors(ErrorCollector.java:309)
grpc-api_1    |         at org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:938)
grpc-api_1    |         at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:585)
grpc-api_1    |         at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:534)
grpc-api_1    |         at com.illumon.iris.db.util.IrisDbGroovySession.updateClassloader(IrisDbGroovySession.java:552)
grpc-api_1    |         at com.illumon.iris.db.util.IrisDbGroovySession.evaluate(IrisDbGroovySession.java:245)
grpc-api_1    |         at com.illumon.iris.db.util.AbstractScriptSession.evaluateScript(AbstractScriptSession.java:27)
grpc-api_1    |         at io.deephaven.grpc_api.console.ConsoleServiceGrpcImpl.lambda$null$7(ConsoleServiceGrpcImpl.java:114)
grpc-api_1    |         at com.illumon.util.locks.FunctionalLock.doLockedInterruptibly(FunctionalLock.java:47)
grpc-api_1    |         at io.deephaven.grpc_api.console.ConsoleServiceGrpcImpl.lambda$null$8(ConsoleServiceGrpcImpl.java:108)
grpc-api_1    |         at io.deephaven.grpc_api.session.SessionState$ExportBuilder.lambda$submit$1(SessionState.java:941)
grpc-api_1    |         at io.deephaven.grpc_api.session.SessionState$ExportObject.doExport(SessionState.java:585)
grpc-api_1    |         at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
grpc-api_1    |         at java.util.concurrent.FutureTask.run(FutureTask.java:266)
grpc-api_1    |         at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
grpc-api_1    |         at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
grpc-api_1    |         at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
grpc-api_1    |         at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
grpc-api_1    |         at java.lang.Thread.run(Thread.java:748)

It would be nice to be able to have some more confidence that our scripts worked if we could automatically test them.