Documentation about Java 8 / MethodHandle in Android support

[JuanMorenoDeveloper]

Hi guys!

Regarding this Twitter thread with @raphw where Jake Wharton
mentions the requirements to better Java 8 support in Android. I suggest add a specific entry in the documentation about it.

Affected versions: Android with minSdk<26, Mockito v3.5.0

• The mockito message in the stacktrace have useful information, but it didn't help
• The problematic code (if that's possible) is copied here;
  Note that some configuration are impossible to mock via Mockito
• Provide versions (mockito / jdk / os / any other relevant information)
• Provide a Short, Self Contained, Correct (Compilable), Example of the issue
  (same as any question on stackoverflow.com)
• Read the contributing guide

[JuanMorenoDeveloper]

I added this PR #2031 to solve this issue