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

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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