Revert "[maven-release-plugin] prepare release 6.2.0-ga1"

This reverts commit fdf162490473d1f80a8b1b03e3904384f0527ef3.
Revert "Prepare 6.2.0-ga1 release."

This reverts commit e8b302f2c37eca7a31b3bc2fbec7316f36e7895e.