languages: add guarani (#2603)

* spanish: some necessary, minor rewording for new background sync strings

* en: fix unmetered network typo

* languages: add guarani

Adds strings_gn.arb file.

* fix: remove `,` from beginning and end of file

* tl_constant: add `gn` value

* flags: add guarani (PY) flag

Adds _gn.png_ file.

* languages: add guarani

* localeCountryCode: fix guarani value to 3 letters (grn); making it cohesive with all others

* res/values: replace strings_gn.arb file for appropriate one

* guarani: remove unnecessary `,` at the beginning and end of file

* guarani: fix a lot of syntax errors...

* guarani: remove all remaining trails of Spanish translation; fix all wrongly translated `${}` values back to English

* fix: gn translation

* ci: add ci check for translations

* Update .github/workflows/are_translations_sane.yml

* res/values: adds fixed `strings_gn.arb` file

* res/values: undoes wrong GN=>ES translations on file

* res/values: fix missing `}` for `strings_gn.arb`

* res/values: adds revised `strings_gn.arb` file

* res/values: adds revised `strings_gn.arb` file

* res/values: adds revised `strings_gn.arb` file

---------

Co-authored-by: Czarek Nakamoto <cyjan@mrcyjanek.net>
Co-authored-by: Omar Hatem <omarh.ismail1@gmail.com>

tool/utils/translation/translation_constants.dart

@@ -1,6 +1,6 @@
 const defaultLang = "en";
 const langs = [
-  "ar", "bg", "cs", "de", "en", "es", "fr", "ha", "hi", "hr", "hy", "id", "it",
+  "ar", "bg", "cs", "de", "en", "es", "fr", "gn", "ha", "hi", "hr", "hy", "id", "it",
   "ja", "ko", "my", "nl", "pl", "pt", "ru", "th", "tl", "tr", "uk", "ur", "yo",
   "vi", "zh-cn" // zh, but Google Translate uses zh-cn for Chinese (Simplified)
 ];