deps: update dependency org.graalvm.buildtools:native-maven-plugin to v0.9.21 (#2634)

* deps: update dependency org.graalvm.buildtools:native-maven-plugin to v0.9.21 * 🦉 Updates from OwlBot post-processor See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md --------- Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: renovate-bot

samples/native-image-sample/pom.xml

@@ -121,7 +121,7 @@
  <plugin>
  <groupId>org.graalvm.buildtools</groupId>
  <artifactId>native-maven-plugin</artifactId>
- <version>0.9.20</version>
+ <version>0.9.21</version>
  <extensions>true</extensions>
  <configuration>
  <mainClass>com.example.bigquery.NativeImageBigquerySample