Fix migration errors on form_submissions

[ryanmitchell]

This PR updates the form_submissions update migration to check it needs to be run. It also ensures we only drop the foreign key if it exists.

Closes: #323
Fixes: #285 (comment)

[DanielDarrenJones]

@ryanmitchell I seem to be getting an issue when running this:

   INFO  Running migrations.  

  2024_05_15_100000_modify_form_submissions_id ........................................................................................... 25ms DONE
  2024_06_11_183314_drop_status_on_entries ................................................................................................ 5ms DONE
  2024_06_11_183314_relate_form_submissions_by_handle .................................................................................... 13ms FAIL

   Error 

  Class "Doctrine\DBAL\Driver\AbstractMySQLDriver" not found

  at vendor/laravel/framework/src/Illuminate/Database/PDO/MySqlDriver.php:8
      4▕ 
      5▕ use Doctrine\DBAL\Driver\AbstractMySQLDriver;
      6▕ use Illuminate\Database\PDO\Concerns\ConnectsToDatabase;
      7▕ 
  ➜   8▕ class MySqlDriver extends AbstractMySQLDriver
      9▕ {
     10▕     use ConnectsToDatabase;
     11▕ 
     12▕     /**

      +5 vendor frames 

  6   database/migrations/2024_06_11_183314_relate_form_submissions_by_handle.php:62
      Illuminate\Database\Connection::getDoctrineSchemaManager()

  7   database/migrations/2024_06_11_183314_relate_form_submissions_by_handle.php:31
      Statamic\Eloquent\Database\BaseMigration@anonymous\/Users/danieljones/Dev/pelorus-travel/database/migrations/2024_06_11_183314_relate_form_submissions_by_handle.php:9$1fb::listTableForeignKeys("form_submissions")

However, if I run the migration a second time after it succeeds:

   INFO  Running migrations.  

  2024_06_11_183314_relate_form_submissions_by_handle  3ms DONE

[ryanmitchell]

I guess you need doctrine/dbal installed for it to work.
Back to the drawing board.

[ryanmitchell]

@DanielDarrenJones this work any better? 0d251c7

[DanielDarrenJones]

@ryanmitchell that seems to run fine against my project! :)

[ryanmitchell]

@DanielDarrenJones can I just check you had cleared the previous migration entry from your migrations table before testing?

[DanielDarrenJones]

@DanielDarrenJones can I just check you had cleared the previous migration entry from your migrations table before testing?

Yeah I ran from a backup of our live statamic 4 project (we were just in the process of deploying v5 so this was perfect timing)

[ryanmitchell]

@DanielDarrenJones awesome thanks for confirming