l10n: Add full Irish translation (ga.po)

- Added complete Irish translation (ga.po).
- Added entry for Irish in po/TEAMS.
- Corrected email format and removed trailing whitespace.
- Translated new strings from Git 2.50.0-rc0

Signed-off-by: Aindriú Mac Giolla Eoin <aindriu80@gmail.com>

Author: aindriu80

po/TEAMS

@@ -29,6 +29,10 @@ Repository:	https://github.com/jnavila/git
 Leader:		Jean-Noël Avila <jn.avila@free.fr>
 Members:	Sébastien Helleu <flashcode@flashtux.org>
 
+Language:	ga (Irish)
+Repository:	https://github.com/aindriu80/git-po
+Members:	Aindriú Mac Giolla Eoin <aindriu80@gmail.com>
+
 Language:	id (Indonesian)
 Repository:	https://github.com/bagasme/git-po
 Leader:		Bagas Sanjaya <bagasdotme@gmail.com>