Jira does not release home directory lock if DB connection refused on startup

Problem: If, when verifying the database connection settings on startup, Jira is unable to connect to the remote database and logs messages "cannot create Poolable Connection Factory", and/or "connection refused: connect". It will retry repeatedly. If it is still unable to connect after 5 mins or so, it will restart – but in restarting it does not remove the lock on the home directory.

This makes jira unusable until the lock file is deleted.

Fix: After the DB connection attempts time out, and before restart, remove the home directory lock.

This happens on restart when Windows update runs, so it may be affected by or affect JRA-17768 or JRA-20311.