deps: update dependency com.google.auto.value:auto-value-annotations to v1.8.1 (#215)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [com.google.auto.value:auto-value-annotations](https://togithub.com/google/auto) | `1.8` -> `1.8.1` | [![age](https://badges.renovateapi.com/packages/maven/com.google.auto.value:auto-value-annotations/1.8.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.auto.value:auto-value-annotations/1.8.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.auto.value:auto-value-annotations/1.8.1/compatibility-slim/1.8)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.auto.value:auto-value-annotations/1.8.1/confidence-slim/1.8)](https://docs.renovatebot.com/merge-confidence/) |

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build.gradle

@@ -40,7 +40,7 @@ ext {
   libraries = [
       javax_annotations: 'javax.annotation:javax.annotation-api:1.3.2',
       auto_value: 'com.google.auto.value:auto-value:1.8',
-      auto_value_annotations: 'com.google.auto.value:auto-value-annotations:1.8',
+      auto_value_annotations: 'com.google.auto.value:auto-value-annotations:1.8.1',
       guava: 'com.google.guava:guava:30.1.1-android',
       jsr305: 'com.google.code.findbugs:jsr305:3.0.2',
       error_prone_annotations: 'com.google.errorprone:error_prone_annotations:2.6.0',