Update dependency org.testcontainers:junit-jupiter to v1.21.3 (#1439)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.testcontainers:junit-jupiter](https://java.testcontainers.org)
([source](https://redirect.github.com/testcontainers/testcontainers-java))
| `1.21.2` -> `1.21.3` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/org.testcontainers:junit-jupiter/1.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.testcontainers:junit-jupiter/1.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.testcontainers:junit-jupiter/1.21.2/1.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.testcontainers:junit-jupiter/1.21.2/1.21.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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> Some dependencies could not be looked up. Check the Dependency
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---

### Release Notes

<details>
<summary>testcontainers/testcontainers-java
(org.testcontainers:junit-jupiter)</summary>

###
[`v1.21.3`](https://redirect.github.com/testcontainers/testcontainers-java/releases/tag/1.21.3)

[Compare
Source](https://redirect.github.com/testcontainers/testcontainers-java/compare/1.21.2...1.21.3)

##### What's Changed

- Update testcontainers/sshd version to 1.3.0
([#&#8203;10377](https://redirect.github.com/testcontainers/testcontainers-java/issues/10377))
[@&#8203;eddumelendez](https://redirect.github.com/eddumelendez)
- Support docker/mcp-gateway image
([#&#8203;10378](https://redirect.github.com/testcontainers/testcontainers-java/issues/10378))
[@&#8203;eddumelendez](https://redirect.github.com/eddumelendez)
- Update testcontainers version to 1.21.2
([#&#8203;10369](https://redirect.github.com/testcontainers/testcontainers-java/issues/10369))
[@&#8203;github-actions](https://redirect.github.com/github-actions)
- Update docs version to 1.21.2
([#&#8203;10368](https://redirect.github.com/testcontainers/testcontainers-java/issues/10368))
[@&#8203;github-actions](https://redirect.github.com/github-actions)

</details>

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integration-tests/pom.xml

@@ -56,7 +56,7 @@
     <dependency>
       <groupId>org.testcontainers</groupId>
       <artifactId>junit-jupiter</artifactId>
-      <version>1.21.2</version>
+      <version>1.21.3</version>
       <scope>test</scope>
       <exclusions>
         <exclusion>