[SettingsCard] Accesibility improvements

[niels9001]

This PR:

• Updates the correct on hover brush in high contrast mode, addressing: [SettingsCard] No text shown OnPressed in HighContrast mode #271
• Updates the AutomationPeer so that the SettingsCard identifies as a Button when IsClickEnabled, addressing: SettingsCard isn't accessible with Voice Access #283 and Unable to invoke SettingsCard when Narrator is on (Scan mode) #262
• Moved some logic identifying the name Narrator uses in the AutomationPeer.

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Wrong high contrast color (#283)
Before (issue #271):

After:

Before (issue #283):

After:

Before (issue #262)
Narrator: Focus on card title, group => click event doesn't work

After:
Narrator: Card title, button => click event works