For #8947 - Lint check for licenses in Kotlin/Java source files

[juan-goncalves]

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• Tests: This PR includes thorough tests or an explanation of why it does not
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• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

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[liuche]

@juan-goncalves can you rebase this to resolve the conflicts? Thanks!

[juan-goncalves]

Hey @liuche! Done, conflicts resolved

[ekager]

thanks so much for your PR @juan-goncalves this looks great!

[liuche]

Seems like some kind of toolchain error, so I'll retry:

TEST: classMethod
[task 2020-10-16T21:53:41.113Z] *** java.lang.instrument ASSERTION FAILED ***: "!errorOutstanding" with message can't create byte arrau at JPLISAgent.c line: 813