Change android gradle source compatibility definition from 11 to 17

[mikehardy]

Shouldn't be a breaking change since we already require JDK17 or we hard-fail builds...

Not sure when react-native started using AGP8+ but it may be that react-native-firebase will actually work with older react-natives using AGP7 after the PR addressing this. Not that it would imply support, but it wouldn't outright fail the build for folks attempting that

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@nrtrjmly Interesting! that's a subtle interaction - missed that in previous analysis of this problem. AGP8+ has been in use long enough that I hadn't tested back far enough to attempt AGP<=8

Indeed it is kind-of-a-bug to have 11 listed for source compatibility since the code is no longer compatible with it. That should have been bumped to 17 at the same time the JDK17+ source feature was added

Originally posted by @mikehardy in #7816