Improve GRADLE build Performance

[shisheng-1]

Incremental compilation. Gradle recompile only the classes that were affected by a change. This feature is the default since Gradle 4.10. For an older versions, we can activate it by setting options.incremental = true.

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If there are any inappropriate modifications in this PR, please give me a reply and I will change them.

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[shisheng-1]

@googlebot I signed it!

@googlebot I signed it!