Fixed #35359 -- Made autodetector add fields referenced by GeneratedField.expression before it.

[DevilsAutumn]

Trac ticket number

Ticket #35359

Branch description

While adding a GeneratedField field along with a new field, the AddField operations were being generated in the wrong order due to which it was breaking the migrations. The AddField operation for fields referenced by GeneratedField.expression should be added before the GeneratedField itself.

My solution modifies the _generate_added_field method in the autodetector to check if a field is a GeneratedField, then extract the referenced fields from .expression and recursively call _generate_added_field to add AddField operation for the fields referenced by .expression before GeneratedField.

Checklist

• This PR targets the main branch.
• The commit message is written in past tense, mentions the ticket number, and ends with a period.
• I have checked the "Has patch" ticket flag in the Trac system.
• I have added or updated relevant tests.
• I have added or updated relevant docs, including release notes if applicable.
• For UI changes, I have attached screenshots in both light and dark modes.

[sarahboyce]

Thank you @DevilsAutumn this looks good ⭐

Can you add a release note to 5.0.5? This will be included in the upcoming release 😁

[nessita]

Looks great! I pushed small edits, will merge and backport when CI is green.