Add Guava 31+ support by treating @ParametricNullness as @Nullable

[lazaroclapp]

Guava versions from 31.0 onwards do away with annotating methods as
returning or taking @Nullable if nullability depends on the type
parameter. Instead adopting JSpecify semantics for precise handling
of type parameters.

For compatibility (with Kotlin, among other tools), Guava still marks
such returns and arguments specially as @ParametricNullness.

While imprecise, we can handle Guava as annotated code to at least the
same level as we did previously, by treating @ParametricNullness as
an alias for @Nullable, until we have full type parameter / generics
support within NullAway.

To test this change without bumping our own Guava dependency, we
introduce a new test target: :guava-recent-unit-tests.

Additionally, since there are actually multiple instances of
@ParametricNullness in Guava (one per subpackage), we hard-code
a check for com.google.common.*.ParametricNullness in our core
isNullableAnnotation(...) check.

An alternative would be to extend -XepOpt:NullAway:CustomNullableAnnotations
to allow simple names or regular expressions, but that would make
the mechanism more costly in common case.

See also: #628, google/guava#6126

[coveralls]

Pull Request Test Coverage Report for Build #896

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 92.488%

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Totals
Change from base Build #893:	0.02%
Covered Lines:	4802
Relevant Lines:	5192

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💛 - Coveralls

[msridhar]

LGTM! Approved assuming comment is addressed before landing

[msridhar]

If we want coverage from tests in this module to be included as part of the overall code coverage report (sent to Coveralls), we should add an implementation dependence on this module here:

NullAway/code-coverage-report/build.gradle

Lines 90 to 95 in 4cbd781

	dependencies {
	implementation project(':nullaway')
	implementation project(':jar-infer:jar-infer-lib')
	implementation project(':jar-infer:nullaway-integration-test')
	implementation project(':jdk17-unit-tests')
	}

[lazaroclapp]

Done. Also making sure this builds on all JDKs we support.