Moved 'Edit review' user preferences into the 'Recent changes' tab

As 'Edit review' preferences control how latest revisions are shown,
'Recent changes' tab seems to be the right one to move it to. Removed
qqq messages as well.

Bug: 63576
Change-Id: I2c2b08646da6bde2c7b62a9fc4d42cc610d3e690