Bump org.testcontainers:testcontainers-bom

Bumps the build-dependencies group with 1 update in the / directory: [org.testcontainers:testcontainers-bom](https://github.com/testcontainers/testcontainers-java).


Updates `org.testcontainers:testcontainers-bom` from 1.20.6 to 1.21.0
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.20.6...1.21.0)

---
updated-dependencies:
- dependency-name: org.testcontainers:testcontainers-bom
  dependency-version: 1.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: build-dependencies
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

build/parents/build/pom.xml

@@ -134,7 +134,7 @@
         <version.junit-platform-suite-engine>1.10.0</version.junit-platform-suite-engine>
         <version.org.osgi.core>6.0.0</version.org.osgi.core>
         <!-- Make sure to update Ryuk container version in `ryuk.Dockerfile` whenever updating testcontainers to align it with the lib. -->
-        <version.testcontainers>1.20.6</version.testcontainers>
+        <version.testcontainers>1.21.0</version.testcontainers>
 
         <version.org.hamcrest>3.0</version.org.hamcrest>
         <version.org.mockito>5.17.0</version.org.mockito>