Bump com.approvaltests:approvaltests from 18.7.1 to 21.0.0 (#242)

Bumps [com.approvaltests:approvaltests](https://github.com/approvals/ApprovalTests.Java) from 18.7.1 to 21.0.0.
- [Release notes](https://github.com/approvals/ApprovalTests.Java/releases)
- [Commits](approvals/ApprovalTests.Java@18.7.1...21.0.0)

---
updated-dependencies:
- dependency-name: com.approvaltests:approvaltests
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

pom.xml

@@ -91,7 +91,7 @@
         <dependency>
             <groupId>com.approvaltests</groupId>
             <artifactId>approvaltests</artifactId>
-            <version>18.7.1</version>
+            <version>21.0.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>