Revert "[maven-release-plugin] prepare release 6.2.1"

This reverts commit 89e154c4800976b8d153bd4ac25a77d9b17c52f6.
Revert "[maven-release-plugin] prepare for next development iteration"

This reverts commit f4373fe313fc8ed8aebe7c922a139d8ad616716a.
Revert "[maven-release-plugin] prepare release 6.2.1"

This reverts commit a200360942de7ab96b6dba1ad810b37ec8dca08a.
[maven-release-plugin] prepare release 6.2.1