[Android] 'Close Keyman' button is not configurable for other apps that use Keyman Engine

[mcdurdin]

Describe the bug
The Close Keyman button in the language switcher is not configurable or translatable, which is necessary for 3rd party apps that use this.

This is part of a larger issue of i18n and customisability of strings in Keyman Engine. I suggest we look at addressing this as part of the i18n work in 13.0 or 14.0.

Screenshots

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Android:

• Device: Nokia 3
• OS: Android 9
• Keyman version 12.0.x

[darcywong00]

The string comes from /android/KMEA/app/src/main/res/values/strings.xml

<string name="label_close_keyman" translatable="false">Close Keyman</string>

Can an external app define
values-cre/strings.xml to localize the strings?

[darcywong00]

This will be done as part of #809