Settings: Re-enable WebViewAppPickerTest#testNotFinishedIfAdmin

Since the time the test was ignored, this tests seems to have
self-resolved and now passes.

Bug: b/313615637
Test: atest SettingsRoboTests:com.android.settings.webview.WebViewAppPickerTest#testNotFinishedIfAdmin
Flag: TEST_ONLY
Change-Id: I3cd0595fd1a89ee944cd6c8e650c84b4ecdeb99f