Fix bug where it was attempting to use a null parent span

[matt-richardson]

Background

While investigating logs, i spotted:

[2024-09-13 01:50:49,249]  ERROR - y.server.TeamCityBuildListener - {teamcity.build.id=14082131, teamcity.root.build.id=14082074} - Exception in Build Finish caused by: java.lang.NullPointerException: Cannot invoke "io.opentelemetry.context.ImplicitContextKeyed.storeInContext(io.opentelemetry.context.Context)" because "value" is nullnull, with message: Cannot invoke "io.opentelemetry.context.ImplicitContextKeyed.storeInContext(io.opentelemetry.context.Context)" because "value" is null, and stacktrace: [io.opentelemetry.context.Context.with(Context.java:174), com.octopus.teamcity.opentelemetry.server.helpers.OTELHelperImpl.createTransientSpan(OTELHelperImpl.java:68), com.octopus.teamcity.opentelemetry.server.TeamCityBuildListener.createBlockMessageSpan(TeamCityBuildListener.java:349), com.octopus.teamcity.opentelemetry.server.TeamCityBuildListener.createBuildStepSpans(TeamCityBuildListener.java:324), com.octopus.teamcity.opentelemetry.server.TeamCityBuildListener.buildFinishedOrInterrupted(TeamCityBuildListener.java:189), com.octopus.teamcity.opentelemetry.server.TeamCityBuildListener.buildInterrupted(TeamCityBuildListener.java:170), jdk.internal.reflect.GeneratedMethodAccessor543.invoke(Unknown Source), java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43), java.base/java.lang.reflect.Method.invoke(Method.java:568), jetbrains.buildServer.util.EventDispatcher.invokeListeners(EventDispatcher.java:157), jetbrains.buildServer.util.EventDispatcher.lambda$dispatch$0(EventDispatcher.java:134), jetbrains.buildServer.util.NamedThreadFactory.executeWithNewThreadName(NamedThreadFactory.java:76), jetbrains.buildServer.util.EventDispatcher.dispatch(EventDispatcher.java:134), jetbrains.buildServer.serverSide.ServerSideEventDispatcher.superDispatch(ServerSideEventDispatcher.java:6), jetbrains.buildServer.serverSide.ServerSideEventDispatcher.lambda$dispatch$0(ServerSideEventDispatcher.java:3), jetbrains.buildServer.serverSide.impl.auth.SecurityContextImpl.runAs(SecurityContextImpl.java:5), jetbrains.buildServer.serverSide.impl.auth.SecurityContextImpl.runAsUnchecked(SecurityContextImpl.java:25), jetbrains.buildServer.serverSide.impl.auth.SecurityContextImpl.runAsSystemUnchecked(SecurityContextImpl.java:53), jetbrains.buildServer.serverSide.ServerSideEventDispatcher.dispatch(ServerSideEventDispatcher.java:12), jetbrains.buildServer.util.EventDispatcher$2.invoke(EventDispatcher.java:82), jdk.proxy3/jdk.proxy3.$Proxy46.buildInterrupted(Unknown Source), jetbrains.buildServer.serverSide.impl.BaseRunningBuild.finishWithPatchedTreadName(BaseRunningBuild.java:274), jetbrains.buildServer.serverSide.impl.BaseRunningBuild.finish(BaseRunningBuild.java:100), java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804), java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136), java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635), java.base/java.lang.Thread.run(Thread.java:833)]

Results

Looks like it was possible to get a null parent span, which likely would cause a bunch of pain.

I've also added better logging around the main entry points, so errors will go into the proper log file

How to review this PR

Pre-requisites

• I have considered informing or consulting the right people
• I have considered appropriate testing for my change.

[matt-richardson]

[sc-87109]