ProgressCategory: update title style for consistency

 * Update progress category title text color from colorAccent to
   colorSecondary
 * Capitalize the title

Test: make Settings, open `Pair new device` (Bluetooth) settings,
verify title color is textColorSecondary and text is capitalized.

Change-Id: I2d31d14279782b58d5b7c761aba6b683bb337b7d
Signed-off-by: Timi <timi.rautamaki@gmail.com>