Fix import project CE vs EE

What does this MR do?

Reverting missing logic for selecting (EE) CI/CD for external repo. See #335045 (comment 623042067) - basically all the weirdness happened because we were selecting the wrong importing option, though the UI looks very similar in both cases, the differences happen in the BE. This should also fix #335678 (closed).

Does this MR meet the acceptance criteria?

Conformity

• I have included changelog trailers, or none are needed. (Does this MR need a changelog?)
• I have added/updated documentation, or it's not needed. (Is documentation required?)
• I have properly separated EE content from FOSS, or this MR is FOSS only. (Where should EE code go?)
• I have added information for database reviewers in the MR description, or it's not needed. (Does this MR have database related changes?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.
• This change is backwards compatible across updates, or this does not apply.

Related to #335045 (closed) & #335678 (closed)