Bump testcontainers.version from 1.17.6 to 1.21.1 (#865)

Bumps `testcontainers.version` from 1.17.6 to 1.21.1.

Updates `org.testcontainers:consul` from 1.17.6 to 1.21.1
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.17.6...1.21.1)

Updates `org.testcontainers:mockserver` from 1.17.6 to 1.21.1
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.17.6...1.21.1)

Updates `org.testcontainers:junit-jupiter` from 1.17.6 to 1.21.1
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.17.6...1.21.1)

---
updated-dependencies:
- dependency-name: org.testcontainers:consul
  dependency-version: 1.21.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.testcontainers:mockserver
  dependency-version: 1.21.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
- dependency-name: org.testcontainers:junit-jupiter
  dependency-version: 1.21.1
  dependency-type: direct:development
  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]

pom.xml

@@ -27,7 +27,7 @@
 		<spring-cloud-deployer.version>2.8.3</spring-cloud-deployer.version>
 		<spring-cloud-openfeign.version>4.3.1-SNAPSHOT</spring-cloud-openfeign.version>
 		<spring-cloud-stream.version>4.3.1-SNAPSHOT</spring-cloud-stream.version>
-		<testcontainers.version>1.17.6</testcontainers.version>
+		<testcontainers.version>1.21.1</testcontainers.version>
 		<mockserverclient.version>5.15.0</mockserverclient.version>
 	</properties>