Add built in support for using GuardedBy annotation with a StampedLock

### Description of the problem / feature request:
Add built in support for using [GuardedBy](https://github.com/google/error-prone/blob/master/docs/bugpattern/GuardedBy.md) annotation with a [StampedLock](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/concurrent/locks/StampedLock.html).

### Feature requests: what underlying problem are you trying to solve with this feature?
Using error-prone compile-time checks to ensure that fields and methods are protected by a lock however error-prone doesn't support using the GuardedBy annotation with a StampedLock.

### What version of Error Prone are you using?
[v2.3.4](https://github.com/google/error-prone/releases/tag/v2.3.4)

###  Have you found anything relevant by searching the web?
I have done multiple searches on this and looked through the code base. From what I can see `StampedLock` is never mentioned.

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#### Workaround:
For those reading that would like to use `GuardedBy` with a `StampedLock` it is currently possible to use `new StampedLock().asReadWriteLock();` to get around this issue, however, this is an imperfect solution as it prevents usage of the extra features such as optimistic reads which come with `StampedLock`.