Remove dependencies on Aliyun Maven repositories when migrating to GCP

[dillon-zheng]

Some parts of the codebase currently modify the Maven repository configuration to point to https://maven.aliyun.com/repository/central (see: https://github.com/PingCAP-QE/ci/blob/main/jenkins/pipelines/ci/tidb/tidb_ghpr_common_test.groovy#L563).