[Designer] removing a relation tries to remove the internal relation regardless of if the configuration storage is enabled

[williamdes]

Describe the bug

Removing relations on the Designer tries to remove the internal relation even if the configuration storage is not enabled

To Reproduce

Steps to reproduce the behavior:

1. Go to Designer
2. Remove a relation

Expected behavior

Remove it without trying to remove the internal relation

Server configuration

• phpMyAdmin version: 5.1

[williamdes]

This should explain reports of:

Warning: Undefined array key "relation"
#2 .\libraries\classes\Database\Designer\Common.php(18): callControllerForRoute
#1 .\libraries\classes\Database\Designer\Common.php(187): index
#0 .\libraries\classes\Database\Designer\Common.php(142): removeRelation

and

Notice: Undefined index: foreign_keys_data
#4 ./libraries/classes/Relation.php(181): getHtmlForInsertEditRow
#3 ./libraries/classes/Relation.php(3455): getHtmlForInsertEditFormColumn
#2 ./libraries/classes/Relation.php(3242): getNullColumn
#1 ./libraries/classes/Relation.php(545): getNullifyCodeForNullColumn
#0 ./libraries/classes/Relation.php(575): searchColumnInForeigners

[williamdes]

This is also because the UI does not remove the relation and so the user can re-try to delete the relation, making the second part of the code be triggered.
This issue will be about the front and back end of this issue