Bump testcontainers.version from 1.20.3 to 1.20.4

Bumps `testcontainers.version` from 1.20.3 to 1.20.4.

Updates `org.testcontainers:testcontainers-bom` from 1.20.3 to 1.20.4
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.20.3...1.20.4)

Updates `org.testcontainers:testcontainers` from 1.20.3 to 1.20.4
- [Release notes](https://github.com/testcontainers/testcontainers-java/releases)
- [Changelog](https://github.com/testcontainers/testcontainers-java/blob/main/CHANGELOG.md)
- [Commits](testcontainers/testcontainers-java@1.20.3...1.20.4)

---
updated-dependencies:
- dependency-name: org.testcontainers:testcontainers-bom
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.testcontainers:testcontainers
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

bom/application/pom.xml

@@ -195,7 +195,7 @@
         <avro.version>1.12.0</avro.version>
         <apicurio-registry.version>2.6.5.Final</apicurio-registry.version>
         <apicurio-common-rest-client.version>0.1.18.Final</apicurio-common-rest-client.version> <!-- must be the version Apicurio Registry uses -->
-        <testcontainers.version>1.20.3</testcontainers.version> <!-- Make sure to also update docker-java.version to match its needs -->
+        <testcontainers.version>1.20.4</testcontainers.version> <!-- Make sure to also update docker-java.version to match its needs -->
         <docker-java.version>3.4.0</docker-java.version> <!-- must be the version Testcontainers use: https://central.sonatype.com/artifact/org.testcontainers/testcontainers -->
         <!-- Check the compatibility matrix (https://github.com/opensearch-project/opensearch-testcontainers) before upgrading: -->
         <opensearch-testcontainers.version>2.0.2</opensearch-testcontainers.version>