Accessibility : AztecText focuses on hover

[jd-alexander]

Expected

That the user has to tap the AztecText control for it to gain focus when using TalkBack.

Parent issue wordpress-mobile/gutenberg-mobile#918

Observed

Once the user hovers on the AztecText control when TalkBack is on, the view is focused.

Reproduced

1. Enable TalkBack.
2. Hover over the example content within the AztecText view.
3. See the blinking cursor.

Tested on Google Pixel 4 XL, Android 10, WPAndroid develop ()