[2076619] Could not create deployment with an unknown git repo and builder image build strategy

Description of problem:
When the user enters an unknown git repo like https://mysupersecretgit.example.com/org/repo and keep the Builder Image it is not possible to create the Deployment successfully also if everything else is entered correctly.

The create button is only enabled when switching to Dockerfile and back to Builder image.

Also when switching to Devfile the form could not be submitted when entering a Devfile.

Version-Release number of selected component (if applicable):
4.9 and above

How reproducible:
Always

Steps to Reproduce:
CASE A
1. Switch to developer perspective, add page > import from Git
2. Enter URL https://mysupersecretgit.example.com/org/repo
3. Select Builder image (node.js for example), enter a name. Now all required fields are filled.

CASE B
1. Switch to developer perspective, add page > import from Git
2. Enter URL https://mysupersecretgit.example.com/org/repo
3. Select Devfile, enter "Devfile", a name. Now all required fields are filled.

Actual results:
CASE A) The user can not import the Deployment

CASE B) Devfile shows an validation error "Devfile not detected". The user can not import the Deployment

Expected results:
CASE A) Could import the Deployment also with Git Type=Other and without switching to Dockerfile and back to Builder Image.

CASE B) The Devfile validation error is fine. We can not fetch Devfiles for unknown providers. If possible we should show another error message if the provider is "Other" and we couldn't load it at all.

The user should also not have the option to submit the form if there is a Devfile error (aka disable 'Create' button).

Additional info:
On 4.9 similar issue happens with the Devfile. When switching from the default Devfile to Builder image and back, the form can be submitted.

When updating the Devfile input again, the form could not be submitted again,