deps: update dependency org.graalvm.buildtools:junit-platform-native to v0.9.21 (#1704)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [org.graalvm.buildtools:junit-platform-native](https://github.com/graalvm/native-build-tools) | `0.9.20` -> `0.9.21` | [![age](https://badges.renovateapi.com/packages/maven/org.graalvm.buildtools:junit-platform-native/0.9.21/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/org.graalvm.buildtools:junit-platform-native/0.9.21/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/org.graalvm.buildtools:junit-platform-native/0.9.21/compatibility-slim/0.9.20)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/org.graalvm.buildtools:junit-platform-native/0.9.21/confidence-slim/0.9.20)](https://docs.renovatebot.com/merge-confidence/) |

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Author: renovate-bot

samples/native-image-sample/pom.xml

@@ -89,7 +89,7 @@
         <dependency>
           <groupId>org.graalvm.buildtools</groupId>
           <artifactId>junit-platform-native</artifactId>
-          <version>0.9.20</version>
+          <version>0.9.21</version>
           <scope>test</scope>
         </dependency>
       </dependencies>