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

This reverts commit f84d87bc8fd1315d2dd930c10e4b59a2da382b9b.
Revert "[maven-release-plugin] prepare release wso2-wss4j-1.5.11-wso2v7"

This reverts commit 6890345ef1c028c61f62faf1fa28cefba95991d2.