Update Singapore holidays: add en_SG, en_US, th localization

[PPsyrius]

Proposed change

Adds English (en_SG, en_US) and Thai (th) localization for Singapore holidays.

I tried to standardize en_US localization to the common Islamic holiday terms used in this library, i.e. Eid al-Fitr instead of Hari Raya Puasa used in en_SG, so any feedback here would be appreciated.

Note

Thai Public Broadcasting Service (Thai PBS) is used as the primary source for Islamic holidays naming over Thai Wikipedia ones i.e. อีฎิ้ลฟิตริ instead of อีดิลฟิฏร์

Type of change

• New country/market holidays support (thank you!)
• Supported country/market holidays update (calendar discrepancy fix, localization)
• Existing code/documentation/test/process quality improvement (best practice, cleanup, refactoring, optimization)
• Dependency update (version deprecation/pin/upgrade)
• Bugfix (non-breaking change which fixes an issue)
• Breaking change (a code change causing existing functionality to break)
• New feature (new python-holidays functionality in general)

Checklist

• I've followed the contributing guidelines
• I've run make pre-commit, it didn't generate any changes
• I've run make test, all tests passed locally

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00%. Comparing base (112b043) to head (f93eb6c).
Report is 1 commits behind head on dev.

Additional details and impacted files

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  Coverage   100.00%   100.00%           
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  Files          189       189           
  Lines        11479     11483    +4     
  Branches      1795      1795           
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+ Hits         11479     11483    +4     

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[KJhellico]

I tried to standardize en_US localization to the common Islamic holiday terms used in this library, i.e. Eid al-Fitr instead of Hari Raya Puasa used in en_SG, so any feedback here would be appreciated.

I completely agree with en_US standardization! (As I understand, these names, "Hari Raya Puasa" and "Hari Raya Haji", are in fact Malay)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[KJhellico]

LGTM.