Fix E2E admin login failure

[mikkamp]

Created this draft PR to test E2E login on admin page. Not able to reproduce this failure locally.

Added screenshot recording to facilitate troubleshooting, this is what the login screen looks like:

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 65.0%. Comparing base (ed1bc62) to head (9065bd4).

Files with missing lines	Patch %	Lines
...ernal/DependencyManagement/CoreServiceProvider.php	0.0%	1 Missing ⚠️

Additional details and impacted files

@@                        Coverage Diff                         @@
##             fix/connect-to-invalid-ads-id   #2689      +/-   ##
==================================================================
+ Coverage                             62.3%   65.0%    +2.8%     
- Complexity                               0    4656    +4656     
==================================================================
  Files                                  335     812     +477     
  Lines                                 5145   24573   +19428     
  Branches                              1254    1254              
==================================================================
+ Hits                                  3204   15984   +12780     
- Misses                                1769    8417    +6648     
  Partials                               172     172              

Flag	Coverage Δ
js-unit-tests	62.3% <ø> (ø)
php-unit-tests	65.8% <0.0%> (?)

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Files with missing lines	Coverage Δ
...ernal/DependencyManagement/CoreServiceProvider.php	0.0% <0.0%> (ø)

... and 476 files with indirect coverage changes

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[mikkamp]

After using a filter to output the PHP error message, I uncovered the following:

We check return defined( 'WP_CLI' ) && WP_CLI, but that's not the same as checking if the class is available.

[mikkamp]

Just to conclude, we found the culprit was the is_needed function was not running to check the conditions.

The following commit fixes this issue: c0fdbad

Closing this PR, but it has some useful commits to help surface errors in the E2E environment:

• Manually take a screenshot (if placed in the right folder it will be part of the artifacts): 0669161
• Use a filter to output the fatal error from WordPress within the screenshot (couldn't find a way to get direct access to the PHP log file): 952283b