Override getResources in DefaultDeprecatedClassLoader

[blindpirate]

This fixes #10347

In #9898 we introduced a DefaultDeprecatedClassLoader,
which overrides getResource() but not getResources(). This causes some issues.
This PR fixes the issue by correctly overriding getResources() method.

[blindpirate]

Verified the fix by using a local distribution to run the sample provided in https://discuss.gradle.org/t/gradle-5-6-runtimeexception-unable-to-load-faststringservice/32865

[blindpirate]

@big-guy @breskeby I still don't know why so many tests are failing with "cannot delete test dir" error..

[blindpirate]

I spent a lot of time investigating why buildSrc.jar is kept open in this test https://builds.gradle.org/viewLog.html?buildId=26104430& but got no clues.

[blindpirate]

I spent several hours on the leaked file handles, it turns out to be this line, where the released classloader still holds the open file handle to jar file.

I failed to find out a good way to fix it - just an ugly workaround. Please @breskeby take a look at it.