Add tristate permission support for body sensor permission

Currently only states supported for body sensor permissions are allow
and deny. This change adds support for allowing the permission only
while the app is in foreground by adding a new permission only for
background. This structure is similar to the current state for location
permissions.

Test: Manual atest
Change-Id: I8fcab6c0c884b79291586f64fd221e40982bc4c5
Bug: 208305481