Bump com.google.errorprone:error_prone_core from 2.18.0 to 2.20.0 (#474)

Bumps [com.google.errorprone:error_prone_core](https://github.com/google/error-prone) from 2.18.0 to 2.20.0.
- [Release notes](https://github.com/google/error-prone/releases)
- [Commits](google/error-prone@v2.18.0...v2.20.0)

---
updated-dependencies:
- dependency-name: com.google.errorprone:error_prone_core
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

core/build.gradle

@@ -47,9 +47,9 @@ dependencies {
     dependencies {
         errorproneJavac('com.google.errorprone:javac:9+181-r4173-1')
         if (JavaVersion.current().isJava11Compatible()) {
-            errorprone('com.google.errorprone:error_prone_core:2.18.0')
+            errorprone('com.google.errorprone:error_prone_core:2.20.0')
         } else {
-            errorprone('com.google.errorprone:error_prone_core:2.18.0')
+            errorprone('com.google.errorprone:error_prone_core:2.20.0')
         }
     }
 }

springboot/build.gradle

@@ -9,9 +9,9 @@ dependencies {
     dependencies {
         errorproneJavac('com.google.errorprone:javac:9+181-r4173-1')
         if (JavaVersion.current().isJava11Compatible()) {
-            errorprone('com.google.errorprone:error_prone_core:2.18.0')
+            errorprone('com.google.errorprone:error_prone_core:2.20.0')
         } else {
-            errorprone('com.google.errorprone:error_prone_core:2.18.0')
+            errorprone('com.google.errorprone:error_prone_core:2.20.0')
         }
     }
 }