feat: switch to using forked translations

[deborahgu]

we should use our fork of openedx translations for edxapp prod (ec2). not bothering to parameterize this because ec2 is not long for this world.

FIXES: AU-2734

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Make sure that the following steps are done before merging:

• Have a Site Reliability Engineer review the PR if you don't own all of the services impacted.
• If you are adding any new default values that need to be overridden when this change goes live, update internal repos and add an entry to the top of the CHANGELOG.
• Performed the appropriate testing.

[Copilot]

Pull request overview

This PR aims to configure the Atlas translation system to use a forked version of the openedx-translations repository for the edxapp production EC2 deployment. The change adds an environment variable to specify a custom repository and revision when pulling translations.

• Adds ATLAS_OPTIONS environment variable export to configure translation source
• Specifies repository and branch for Atlas translation pulls
• Hardcodes the configuration specifically for EC2 (acknowledged as temporary)

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[Copilot]

The PR description states the intention is to "use our fork of openedx translations," but the repository specified here is "edx/openedx-translations" which appears to be the upstream repository, not a fork. If the goal is to use a forked version, the repository should be changed to point to your organization's fork (e.g., "yourorg/openedx-translations"). Please verify this is the correct repository reference.

Suggested change

	export ATLAS_OPTIONS="--repository=edx/openedx-translations --revision=main"
	export ATLAS_OPTIONS="--repository=yourorg/openedx-translations --revision=main"