Added exempting variable annotations

Partially fixes #2881

Fixes #2947

COPYBARA_INTEGRATE_REVIEW=#2947 from sergeykad:unused_variable a41b7e3
PiperOrigin-RevId: 567376567

Author: sergeykad

core/src/main/java/com/google/errorprone/bugpatterns/UnusedVariable.java

@@ -145,7 +145,8 @@ public final class UnusedVariable extends BugChecker implements CompilationUnitT
           "org.openqa.selenium.support.FindBy",
           "org.openqa.selenium.support.FindBys",
           "org.apache.beam.sdk.transforms.DoFn.TimerId",
-          "org.apache.beam.sdk.transforms.DoFn.StateId");
+          "org.apache.beam.sdk.transforms.DoFn.StateId",
+          "org.springframework.boot.test.mock.mockito.MockBean");
 
   // TODO(ghm): Find a sensible place to dedupe this with UnnecessarilyVisible.
   private static final ImmutableSet<String> ANNOTATIONS_INDICATING_PARAMETERS_SHOULD_BE_CHECKED =