MockitoSession API does not clean up listener when initMocks fails

[mockitoguy]

When initMocks() fails we did not clean up the session listener. This led to a confusing error message on the next attempt to create a session (next test method run). I stumbled upon this problem when attempting to configure TestNG to use strict stubbing (mockito/mockito-testng#1).

In order to fix this cleanly I need to keep the existing functionality that protects the user from forgetting to use 'finishMocking()'. Hence, I still need to throw an exception if the user adds the same listener multiple times. However, in the event that the listener is dirty, I clean it up automatically instead of failing.

[codecov-io]

Codecov Report

Merging #1475 into release/2.x will increase coverage by 0.13%.
The diff coverage is 95.45%.

@@                Coverage Diff                @@
##             release/2.x    #1475      +/-   ##
=================================================
+ Coverage          88.43%   88.56%   +0.13%     
- Complexity          2390     2397       +7     
=================================================
  Files                298      299       +1     
  Lines               6020     6036      +16     
  Branches             729      732       +3     
=================================================
+ Hits                5324     5346      +22     
+ Misses               517      511       -6     
  Partials             179      179

Impacted Files	Coverage Δ	Complexity Δ
...java/org/mockito/internal/exceptions/Reporter.java	93.68% <100%> (ø)	91 <1> (ø)	⬇️
...kito/exceptions/misusing/InjectMocksException.java	100% <100%> (ø)	1 <1> (?)
.../mockito/internal/junit/UniversalTestListener.java	93.54% <100%> (+0.69%)	13 <2> (+2)	⬆️
...kito/internal/framework/DefaultMockitoSession.java	96.15% <100%> (+0.5%)	6 <0> (ø)	⬇️
...mockito/internal/progress/MockingProgressImpl.java	97.53% <90%> (+0.27%)	33 <7> (+4)	⬆️
...ByteBuddyCrossClassLoaderSerializationSupport.java	84% <0%> (+8%)	6% <0%> (ø)	⬇️

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[mockitoguy]

I'm merging this because it blocks mockito/mockito-testng#1. Happy to address code review feedback after this is merged. The change does not involved public API changes, it fixes a bug. All existing tests pass, and the new tests pass, too. Let's ship it!