Upgrade NullAway 0.9.7 -> 0.9.8

[Picnic-Bot]

This PR contains the following updates:

Package	Type	Update	Change
com.uber.nullaway:nullaway		patch	0.9.7 -> 0.9.8
com.uber.nullaway:nullaway	compile	patch	0.9.7 -> 0.9.8

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Release Notes

uber/NullAway

v0.9.8

Compare Source

• Fix false positive involving type parameter @​Nullable annotations (#​609)
• Add config option to register custom @​Generated annotations. (#​600)
• Treat Void formal arguments as @​Nullable (#​613)
• Generalize support for castToNonNull methods using library models (#​614)
• Support for specific libraries/APIs:
  • Support for Preconditions.checkArgument (#​608)
  • Model for com.google.api.client.util.Strings.isNullOrEmpty (#​605)
• Refactoring:
  • Cleanups to AccessPath representation and implementation (#​603)
  • Clean-up: Remove unused fix suggestion code. (#​615)
• Dependency Updates:
  • Update to Checker Framework 3.22.2 (#​610)
• Build / CI tooling for NullAway itself:
  • Add NullAway 0.9.7 as a JMH benchmark (#​602)
  • Update to Error Prone 2.14.0 (#​606)

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[Picnic-Bot]

Suggested commit message:

Upgrade NullAway 0.9.7 -> 0.9.8 (#145)

See:
- https://github.com/uber/NullAway/blob/master/CHANGELOG.md
- https://github.com/uber/NullAway/compare/v0.9.7...v0.9.8