Upgrade/Install: Disable maintenance mode when a core auto-update is skipped.

[costdev]

Additional maintenance mode calls were added to the automatic updates process. However, there is an early return if a 'core' automatic update fails.

Maintenance mode isn't disabled until later in the WP_Automatic_Updater::update() method. This means that maintenance mode may continue to be enabled despite the core update being treated as a skipped update.

This disables maintenance mode before the early return.

Trac ticket: https://core.trac.wordpress.org/ticket/61459

[github-actions]

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Props costdev, peterwilsoncc, hellofromtonya.

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[github-actions]

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[peterwilsoncc]

@costdev Do you have a mini-plugin I can chuck in to mu-plugins to emulate a failed update before and after?

[costdev]

@peterwilsoncc Try this one: https://gist.github.com/costdev/a6a50b492ce664c1365e1a5c6a7e8429

[hellofromtonya]

Using the force failure plugin in mu-plugins and without applying this change, I'm not yet able to reproduce a maintenance mode when updating Core from 6.5.4 to 6.6 Beta 3. @costdev am I missing a step?

[hellofromtonya]

Theoretically and logically, this change makes sense.

It bothers me that I'm not (yet) able to reproduce the issue of the maintenance lock.

[afragen]

I wonder if I’ve been bitten by this in the past in local dev environments. Tonya, my guess is the only way to test is to modify the $upgrade_result to a WP_ERROR.

[costdev]

Committed in r58436.