Remove notification on SAP B&R changes

SoftAP (SAP) configuration changes on B&R will no longer trigger a
notification. This notification was not providing any value to the user:
- It was not specific (what changed)
- It was not actionable

Bug: 307579005
Test: atest -c android.net.wifi.cts.WifiBackupRestoreTest#testCanRestoreSoftApBackupData
Change-Id: I8b04276a23b2304ae2d7f126bc89c22f90c4991a