fix(ar): render fullcalendar in english (backport #26207)

[mergify]

It doesn't work in arabic - doesn't show anything.

Looks like upstream bug, best we can try for now is to render it in
English instead.

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This is an automatic backport of pull request #26207 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of e4ed1b9 has failed:

On branch mergify/bp/version-14-hotfix/pr-26207
Your branch is up to date with 'origin/version-14-hotfix'.

You are currently cherry-picking commit e4ed1b98e4.
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  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   frappe/public/js/frappe/views/calendar/calendar.js

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