feat: migrate away from deprecated graal-sdk dependency to use nativeimage

[mpeddada1]

Merge after googleapis/java-shared-config#815 is released and updated in sdk-platform-java.

According to the graal/sdk CHANGELOG, the GraalVM SDK was split into smaller modules and the use of graal-sdk is deprecated. The new maven configuration to customize native image generation is:

<dependency>
  <groupId>org.graalvm.sdk</groupId>
  <artifactId>nativeimage</artifactId>
  <version>${graalvm.version}</version>
</dependency>

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud