Fix bug #14903618 Developer Options - string changes needed to the Bug report checkbox

- string update as follow:

LABEL

Current string:
- "Power menu bug reports"

Change to:
- "Bug report shortcut"

SECONDARY TEXT

Current string:
- "Include option in power menu for taking a bug report"

Change to:
- "Show a button in Quick Settings for taking a bug report"

Change-Id: Ibc716e1ae0bc3d553601908efd81babd66051d8b