Fix KeyguardDisabledFeaturesActivity disable camera description

CTS Verifier Keyguard Disabled Features#Test_Disable camera issue
Root Cause:
KeyguardDisabledFeaturesActivity#disable camera feature using DevicePolicyManager API to
disable camera, so we cannot see the camera icon on the lower right corner of the screen,
but the test case description said "Please press the Go button to lock the screen. Then
try to open the camera from the lower right corner of the screen. Expected result is you
cannot open the camera from lock screen and it will ask for password instead", no matched
final behavior

Bug: 114177245

Solution:
Change the KeyguardDisabledFeaturesActivity#disable camera description to "press the Go
button to lock the screen. Expected result is you cannot see camera icon on the lower right
corner of the screen, or if there is one, you cannot open the camera using it before you are
asked for a password"

Change-Id: I6ed8c671e36f859695f218ff816172cfe66a8994
Merged-In: I24ce39812d9a094b236558c009bb1d4d31ccc49d
Signed-off-by: weijuncheng <weijuncheng@xiaomi.com>