[MSITE-1033] Improve heuristics to detect inheritance for SCM site URLs

[kwin]

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[kwin]

I still need to look into the failing IT:

Running post-build script: /home/runner/work/maven-site-plugin/maven-site-plugin/target/it/site-inheritance/verify.bsh
staged moduleDirectory index.html has wrong links!
staged subModuleDirectory is missing or not a directory.
incorrect index file in staged subModuleDirectory!
java.nio.file.NoSuchFileException: /home/runner/work/maven-site-plugin/maven-site-plugin/target/it/site-inheritance/webhost.company.com/stage/www/website/sub_module/index.html
	at java.base/sun.nio.fs.UnixException.translateToIOException(UnixException.java:92)
	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:106)
	at java.base/sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:111)
	at java.base/sun.nio.fs.UnixFileSystemProvider.newByteChannel(UnixFileSystemProvider.java:218)
	at java.base/java.nio.file.Files.newByteChannel(Files.java:380)
	at java.base/java.nio.file.Files.newByteChannel(Files.java:432)
	at java.base/java.nio.file.Files.readAllBytes(Files.java:3288)
	at java.base/java.nio.file.Files.readString(Files.java:3366)
	at org.codehaus.plexus.util.BaseFileUtils.fileRead(BaseFileUtils.java:17)
	at org.codehaus.plexus.util.FileUtils.fileRead(FileUtils.java:322)
	at jdk.internal.reflect.GeneratedMethodAccessor46.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:569)
	at bsh.Reflect.invokeMethod(Reflect.java:131)
	at bsh.Reflect.invokeStaticMethod(Reflect.java:95)
	at bsh.Name.invokeMethod(Name.java:793)
	at bsh.BSHMethodInvocation.eval(BSHMethodInvocation.java:69)
	at bsh.BSHPrimaryExpression.eval(BSHPrimaryExpression.java:96)
	at bsh.BSHPrimaryExpression.eval(BSHPrimaryExpression.java:41)
	at bsh.BSHAssignment.eval(BSHAssignment.java:71)
	at bsh.BSHBlock.evalBlock(BSHBlock.java:125)
	at bsh.BSHBlock.eval(BSHBlock.java:75)
	at bsh.BSHBlock.eval(BSHBlock.java:41)
	at bsh.BSHTryStatement.eval(BSHTryStatement.java:80)
	at bsh.Interpreter.eval(Interpreter.java:659)
	at bsh.Interpreter.eval(Interpreter.java:750)
	at bsh.Interpreter.eval(Interpreter.java:739)
	at org.apache.maven.shared.scriptinterpreter.BeanShellScriptInterpreter.evaluateScript(BeanShellScriptInterpreter.java:145)
	at org.apache.maven.shared.scriptinterpreter.ScriptRunner.executeRun(ScriptRunner.java:222)
	at org.apache.maven.shared.scriptinterpreter.ScriptRunner.run(ScriptRunner.java:158)
	at org.apache.maven.plugins.invoker.AbstractInvokerMojo.runPostBuildHook(AbstractInvokerMojo.java:1957)
	at org.apache.maven.plugins.invoker.AbstractInvokerMojo.runBuild(AbstractInvokerMojo.java:1914)
	at org.apache.maven.plugins.invoker.AbstractInvokerMojo.runBuild(AbstractInvokerMojo.java:1584)
	at org.apache.maven.plugins.invoker.AbstractInvokerMojo.lambda$runBuilds$4(AbstractInvokerMojo.java:1346)
	at org.apache.maven.plugins.invoker.JobExecutor.lambda$forEach$0(JobExecutor.java:63)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:840)
Finished post-build script: /home/runner/work/maven-site-plugin/maven-site-plugin/target/it/site-inheritance/verify.bsh
*** end build.log for: site-inheritance/pom.xml ***

Update: Debugging revealed the following distributionMgmt.site.url being used for it/site-inheritance/module and it/site-inheritance-submodule:

1. target/it/site-inheritance/webhost.company.com/deploy/www/website/module
2. target/it/site-inheritance/webhost.company.com/deploy/www/website/sub_module

So in fact those are siblings not nested, seems that the inheritance works a bit differently than outlined in https://maven.apache.org/ref/3-LATEST/maven-model-builder/ (compare with https://maven.apache.org/ref/3-LATEST/maven-model-builder/xref/org/apache/maven/model/inheritance/DefaultInheritanceAssembler.html#L95).

I would argue the expected behaviour is wrong and submodule should not end up below module but next to it!

[jira-importer]

Resolve #1159