deps: update dependency com.google.errorprone:error_prone_annotations to v2.7.1 (#231)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| com.google.errorprone:error_prone_annotations | `2.6.0` -> `2.7.1` | [![age](https://badges.renovateapi.com/packages/maven/com.google.errorprone:error_prone_annotations/2.7.1/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/com.google.errorprone:error_prone_annotations/2.7.1/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/com.google.errorprone:error_prone_annotations/2.7.1/compatibility-slim/2.6.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/com.google.errorprone:error_prone_annotations/2.7.1/confidence-slim/2.6.0)](https://docs.renovatebot.com/merge-confidence/) |

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build.gradle

@@ -43,7 +43,7 @@ ext {
       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',
+      error_prone_annotations: 'com.google.errorprone:error_prone_annotations:2.7.1',
 
       // Testing
       junit: 'junit:junit:4.13.2',