docs(sample): removing unnecessary native-image-support dependency (#681)

For GraalVM native image, GAX provides required metadata. We no longer need native-image-support-java module.

Author: suztomo

tasks/native-image-sample/pom.xml

@@ -80,12 +80,6 @@
     <profile>
       <id>native</id>
       <dependencies>
-        <dependency>
-          <!-- TODO: remove this when it's no longer needed -->
-          <groupId>com.google.cloud</groupId>
-          <artifactId>native-image-support</artifactId>
-          <version>0.13.1</version>
-        </dependency>
         <dependency>
           <groupId>org.junit.vintage</groupId>
           <artifactId>junit-vintage-engine</artifactId>