Add Filipino Localization for the Philippines Holiday Class

[arkid15r]

The vacanza/holidays package currently supports public holidays for the Philippines, as defined in the holidays/countries/philippines.py file. However, the package lacks Filipino translations for the holiday names. It seems we should use fil ISO 639-2 code as described here and here.

The holidays l10n documentation section -- https://holidays.readthedocs.io/en/latest/contributing.html#localization

Some l10n PR examples:

• Add Thailand holidays localization: en_US, th #946
• Add Arabic localization #1341
• Update Vietnam holidays: add th localization #2060
• More PRs w/ l10n label

Personally I would prefer to see fil_PH as the default but en_PH would also work.

@code-leen we'd appreciate your help with this a lot!

[PPsyrius]

@arkid15r I think it might be for the best to just use Tagalog (tl) instead of Filipino (fil) - as that's exactly what the ISO is using here https://www.iso.org/obp/ui/#iso:code:3166:PH

[arkid15r]

Based on my research Philippines has 2 official languages : Filipino and English. Even though Filipino is Tagalog based language it's different (https://en.wikipedia.org/wiki/Filipino_language)

It is a standardized variety of the native language Tagalog,[3] spoken and written in Metro Manila, the National Capital Region, and in other urban centers of the archipelago.[4] The 1987 Constitution mandates that Filipino be further enriched and developed by the other languages of the Philippines.[5]