Strings: Adjust admin-granted notification strings

Per suggestion from UX, adjust the notification title and string, for
notifications about admin-granted location access, to the following:

[title] Location can be accessed
[subtext] Your IT admin is allowing A Sample App to access your location

Test: Manual
Bug: 148631522
Change-Id: I75aa8f7e162714b2bd6e0d4b6dc75bb7fb07ddc6