Properly handle GitLab merge request event in RHTAP pipeline

[mmorhun]

Update deployment task should be skipped in pull request pipeline.
Pipelines as Code has different name of the event for GitHub and GitLab. Take both into account.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[chmeliik]

Pipelines as Code has different name of the event for GitHub and GitLab

Is this documented somewhere or just based on testing?

[mmorhun]

@chmeliik I haven't seen it in the docs, just what PaC substantiated for {{event_type}} in case of GitLab and merge request.