[REF] CoreResources - Simplify disabled component check

[colemanw]

Overview

Code simplification for checking enabled components when fetching entity ref links/filters.

Before

More complex

After

Simpler

Technical Details

Now that component DAOs have a COMPONENT defined, checks like this are much easier.

[civibot]

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[totten]

Code change looks appropriate.

The output of the function appears in crm-l10n.*.js (specifically exporting data to CRM.config.entityRef), so I did some light r-run as follows:

• Login to a demo site.
• Inspect CRM.config.entityRef in default config. Observe that Case is present.
• Disable the CiviCase component. Reinspect CRM.config.entityRef. Observe that Case is missing.
• Enable the CiviCase component. Reinspect CRM.config.entityRef. Observe that Case is restored.

There is some very light coverage via CRM_Core_Resources test.