[configuration] New Project can be created without alias although alias is NOT NULL

[ridz1208]

Describe the bug It is possible to create a new project from the frontend without giving it a valid Alias although the SQL field is set to NOT NULL. It seems like the code stores an empty string in the field to bypass the NOT NULL

Additionally, if the project is then edited to add an alias and saved (saving is successful) and subsequently edited to remove the alias (so go back to empty alias) submitting the form DOES NOT generate any errors, but also DOES NOT clear the alias. A simple reload of the page reveals that the alias is still there...

To Reproduce Steps to reproduce the behaviour (attach screenshots if applicable):

1. Go to the Configuration module -> Projects
2. add a new project with no alias (First bug)
3. add an alias by editing the project
4. try to remove alias and submit (second bug)

What did you expect to happen? In both cases an error should be returned forcing the user to enter an alias for the project