Move mock classes to SQL src/main, which allows other module to use mock classes without depending SQL test jar but SQL jar.
------------------------ Follow this checklist to help us incorporate your contribution quickly and easily: - [x] Format the pull request title like `[BEAM-XXX] Fixes bug in ApproximateQuantiles`, where you replace `BEAM-XXX` with the appropriate JIRA issue, if applicable. This will automatically link the pull request to the issue. - [ ] If this contribution is large, please file an Apache [Individual Contributor License Agreement](https://www.apache.org/licenses/icla.pdf). It will help us expedite review of your Pull Request if you tag someone (e.g. `@username`) to look at it. Post-Commit Tests Status (on master branch) ------------------------------------------------------------------------------------------------ Lang | SDK | Apex | Dataflow | Flink | Gearpump | Samza | Spark --- | --- | --- | --- | --- | --- | --- | --- Go | [](https://builds.apache.org/job/beam_PostCommit_Go_GradleBuild/lastCompletedBuild/) | --- | --- | --- | --- | --- | --- Java | [](https://builds.apache.org/job/beam_PostCommit_Java_GradleBuild/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Apex_Gradle/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Dataflow_Gradle/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Flink_Gradle/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Gearpump_Gradle/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Samza_Gradle/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Spark_Gradle/lastCompletedBuild/) Python | [](https://builds.apache.org/job/beam_PostCommit_Python_Verify/lastCompletedBuild/) | --- | [](https://builds.apache.org/job/beam_PostCommit_Py_VR_Dataflow/lastCompletedBuild/) </br> [](https://builds.apache.org/job/beam_PostCommit_Py_ValCont/lastCompletedBuild/) | [](https://builds.apache.org/job/beam_PostCommit_Python_VR_Flink/lastCompletedBuild/) | --- | --- | --- [ Full content available at: https://github.com/apache/beam/pull/6566 ] This message was relayed via gitbox.apache.org for devnull@infra.apache.org
