Description of problem:

OpenShift Pipelines as Code not submitting pipeline results to GitLab repository in private GitLab instance with relative path in URL.

To have pipelines-as-code work with out GitLab instance, customer require a different way to have the project ID be determined in such cases, e.g. a parameter in the Repository CR, a possibility to set the repo organisation and name or anything comparably.

Potentially, this addition in https://github.com/openshift-pipelines/pipelines-as-code/blob/7663fb1147f1181de5ed42bb6c44053211c43c43/pkg/provider/gitlab/gitlab.go#L143 will fix it

Prerequisites (if any, like setup, operators/versions):

Openshift Pipelines 1.15.2

Steps to Reproduce:

• Detailed steps in Jira comments(internal)

Customer is experiencing issues with Pipeline-as-Code while implementing it in their environment with a private GitLab instance. The basic functionality works fine: Creating a Repository CR, starting PipelineRuns based on webhooks from GitLab, reporting status on Pipeline start. However, subsequent events - especially reporting the result of a PipelineRun back to GitLab - are not propagated to GitLab and the status is not updated to "Finished", but stays on "Running".

Actual results:

 In the PipelineRun,  seeing this event:

cannot set client: GET https://gitlab-xxxx.fin.local/gitlab/api/v4/projects/gitlab/magic/pipeline-as-code: 404 {message: 404 Project Not Found}"

Expected results:

Status should be rightly updated as "finished" and shouldn't show the "404 Project Not Found" event

Reproducibility (Always/Intermittent/Only Once):

Acceptance criteria: 

Definition of Done:

Build Details:

Additional info (Such as Logs, Screenshots, etc):

Similar to https://issues.redhat.com/browse/SRVKP-4470 & https://issues.redhat.com/browse/KONFLUX-5989

But the issue fixed in above jiras was related to GitLab forked repo