Revert "[maven-release-plugin] prepare for next development iteration"

This reverts commit 23e340e399365c66fec1a13728582d5bba297534.
Revert "[maven-release-plugin] prepare release 6.2.0-ga1"

This reverts commit 609f885d3572bd4afeb90ae6a8650b1b3abef2a7.
Revert "Prepare 6.2.0-ga1 release."

This reverts commit f72db5e540bd65f0e716528b9ff1519b55dc8012.