[Physical Keyboard] Fix L18n test bugs

1. update string to match with Markup
2. a space for label keys as suggested

Bug: 387267421
Bug: 387572420
Flag: com.android.settings.keyboard.keyboard_and_touchpad_a11y_new_page_enabled
Test: atest packages/apps/Settings/tests/robotests/src/com/android/settings/inputmethod
Change-Id: I787cf6ff4e15509d669317a0d968235a08b4dc43