Don't create `javac.[sh|bat]` or `org.codehaus.plexus.compiler.javac.JavacCompiler*arguments` in `target/*classes`

[zregvart]

When debug logging is turned on Javac Plexus compiler creates two additional files in target/classes or target/test-classes. These files will be also included in the built artifact, say a JAR file.

This is done here:

plexus-compiler/plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavacCompiler.java

Lines 597 to 598 in f410363

	File commandLineFile =
	new File( config.getOutputLocation(), "javac." + ( Os.isFamily( Os.FAMILY_WINDOWS ) ? "bat" : "sh" ) );

And here:

plexus-compiler/plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavacCompiler.java

Lines 991 to 992 in f410363

	tempFile =
	File.createTempFile( JavacCompiler.class.getName(), "arguments", new File( outputDirectory ) );

Seems that the calls to config.getOutputLocation() need to be replaced with config.getBuildDirectory() in those two instances.

[urld]

I second that. I would expect the same resulting package regardless of whether debugging is enabled or not.
Leaving those files in target/classes can also causes build failures in debug mode when maven-duplicate-finder-plugin is used.

[zregvart]

Thanks for resurrecting this discussion @urld, I've proposed a change in #173 that I think will fix this issue. Feedback welcome!