Bump com.graphql-java:graphql-java-extended-scalars (#1080)

Bumps [com.graphql-java:graphql-java-extended-scalars](https://github.com/graphql-java/graphql-java-extended-scalars) from 16.0.1 to 20.0.
- [Release notes](https://github.com/graphql-java/graphql-java-extended-scalars/releases)
- [Commits](https://github.com/graphql-java/graphql-java-extended-scalars/commits/20.0)

---
updated-dependencies:
- dependency-name: com.graphql-java:graphql-java-extended-scalars
  dependency-type: direct:production
  update-type: version-update:semver-major
...
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Co-authored-by: Ndependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

plugins/gradle/example-client/build.gradle

@@ -18,7 +18,7 @@ dependencies {
 
     implementation "com.graphql-java-kickstart:graphql-spring-boot-starter:11.0.0"
     implementation "com.graphql-java-kickstart:graphiql-spring-boot-starter:11.1.0"
-    implementation "com.graphql-java:graphql-java-extended-scalars:16.0.1"
+    implementation "com.graphql-java:graphql-java-extended-scalars:20.0"
 
     // use the latest available version:
     // https://search.maven.org/artifact/io.github.kobylynskyi/graphql-java-codegen