Revert "deps: update dependency com.googlecode.maven-download-plugin:download-maven-plugin to v1.7.1"

[mpeddada1]

Reverts #2151. Version 1.7.0 introduced a change that broke backward compatibility (download-maven-plugin/download-maven-plugin#246), however failure with caching still exists in 1.7.1 unless we add the skipCache option. Similar failures were also seen in #2228. Holding off on updating this dependency to investigate further.

[sonarqubecloud]

[gapic-generator-java-root] Kudos, SonarCloud Quality Gate passed!   

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[mpeddada1]

@lqiu96 discovered that the CI logs were still using version 1.7.1 of the download-maven-plugin despite being downgraded in this PR. The logs of the Install sdk-platform-java and showcase to local maven repository GA step show:

[INFO] --- download-maven-plugin:1.7.1:wget (download-common-resources-proto) @ gapic-generator-java ---
[INFO] 
[INFO] --- download-maven-plugin:1.7.1:wget (download-pubsub-proto) @ gapic-generator-java ---
[INFO] 

This line references the main branch which prevents the changes in this PR from taking effect.

Commented out this line and cleaning up debug logic results in a successful build.

Since the clirr check needs to run against the main branch, we will merge this PR in with the failing the showcase-clirr check check the downgrade change into main and rebase the failing release PR.

[sonarqubecloud]

[java_showcase_integration_tests] Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information