Move the cron form to a status report item, then link to the form if automated cron is enabled

Problem/Motivation

Follow-up to #2507031-158: Optimize automatic cron subscriber by moving automatic cron to a module →

@catch

I'm not 100% on keeping the form and altering it, we could possibly move that to a status report item, then link to the form if automated cron is enabled.

The cron should not be run when the user clicks "Save configuration" button.

Proposed resolution

Move the cron form to a status report item, then link to the form if automated cron is enabled

Remaining tasks

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User interface changes

1. With automated_cron module disabled, the cron form is disabled at /admin/config/system/cron.
2. In Status report there's a new line under "Cron maintenance tasks" telling to enable the automated_cron module, if disabled, or linking to Automated Cron settings form, if enabled.
3. The former route/link title 'Cron' (in /admin/config/system) renamed to 'Automated Cron'

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4. Rearranged form elements in /admin/config/system/cron to give priority to 'interval' setting.

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API changes

None.

Data model changes

None.