Prevents pipeline creation for builds with more than 50 tags

Ref: #338479 (closed)

What does this MR do?

This MR prevents pipeline creation for builds with more than 50 tags by adding tag limit on syntax validation.

We decided to use 50 tags as a limit after validation on production data and with product.

Why are we doing this?

With our ongoing work to denormalize tags data to our new queuing system it will be almost impossible to find why a build is not picked up by our new queuing system in case it has more than a 50 tags once !65648 (diffs) is merged.

This is why we are surfacing an error to users so they will not abuse our new queuing system and be aware of our new limit for processing build with tags.

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.