Remove workspaces special casing from system_requirements() and fix versions/docs

Now with extra less test failures.

Looks good, slack feedback was addressed in #3 ;)

+++ b/core/modules/system/system.install
@@ -1368,18 +1368,16 @@ function (callable $hook, string $module) use (&$module_list, $update_registry,
+          '@required_min_version' => '9.3.0',

Should this be 9.4.0 given #3290810: Remove updates added prior to 9.4.0 (9.4.4 for ckeditor) and add 9.4.0 database dumps?

Should this be 9.4.0 given #3290810: Remove updates added prior to 9.4.0?

Valid point, but shouldn't that be handled in #3290810: Remove updates added prior to 9.4.0 (9.4.4 for ckeditor) and add 9.4.0 database dumps?

Ahh I forgot we did #3261486: Remove core updates added prior to 9.3.0 and adjust test coverage already, I guess let's just make a note over there to update system_requirements() as well.

Although, is this going to work, given that system_update_last_removed is still set to 8901, so how will system module appear in the updates list if someone tries to upgrade from e.g. 9.0.0?

I think the test needs updating:

    $update_registry->setInstalledVersion('system', 8804);

This is still testing an update from 8.8.

I think user_update_9301 will work here. We are quite lucky that user.module got that update, there is no guarantee we can always detect the difference between minor releases using only required module schema versions.

Addressed #12-#15

Should this be a beta blocker?

+++ b/core/modules/system/system.install
@@ -1368,18 +1368,16 @@ function (callable $hook, string $module) use (&$module_list, $update_registry,
         'description' => t('Updating to Drupal @current_major is only supported from Drupal version @required_min_version or higher. If you are trying to update from an older version, first update to the latest version of Drupal @previous_major. (<a href=":url">Drupal 9 upgrade guide</a>)', [

Should the link text here just say "Drupal upgrade guide"?

Updated the link text.

1. +++ b/core/modules/system/system.install
   @@ -1368,18 +1368,16 @@ function (callable $hook, string $module) use (&$module_list, $update_registry,
   +          '@current_major' => 10,
   

   Probably out of scope here, but why hard-code this instead of getting it from \Drupal::VERSION?

2. #15 Makes me quite nervous. "We are quite lucky" is never something you want to read in a thread like this. ;) Can/should we do anything to ensure our luck holds in the future? Should we open a follow-up about this?

Otherwise, the patch all looks good to me, and confirmed that https://www.drupal.org/docs/upgrading-drupal/drupal-8-and-higher is a valid and helpful docs page for this message to link to. So I'd RTBC, other than the ? on needing a follow-up...

Let's open a followup to discuss #20.2, and we could have a small issue to handle #20.1 as well.

I'll open the follow-ups now, then RTBC this one.

#20.1: #3292490: Use Drupal::VERSION not hard-coded integer for current major version of core
#20.2: #3292492: Explore how to ensure we can always detect the difference between minor releases using module schema versions

Therefore, RTBC.

Thanks!
-Derek