Replace limited connectivity notification after detecting it

No internet notification may be prompted before partial
connectivity being detected. Partial connectivity status will
be set into NAI and prompted in the Setting. Behavior is not
aligned between Setting and notification. Thus, update
notification again if partial connectivity is detected.
Also, sliently show the updated notification if no internet
notification has already been shown to user to prevent alerting
user in short time.

Bug: 130683832
Test: Verified with simulated partial connectivity
Test: atest FrameworksNetTests
Change-Id: Ie16a8ce6e0fa437048e8c1eea240314ca30e9520
Merged-In: I004e78a33689e2208918d4316bcf9a8f50a0bac3
Merged-In: I14385a39d99a45c4a6a50a665f456f589c2f4da3
(cherry picked from commit a5c68348)