feat: Add `incident view` command

Description

Adds incident view command, which in nutshell is similar to issue view. It opens opportunities to display incident-specific information.

Allows to open an incident by either issue URL (https://gitlab.com/OWNER/REPO/-/issues/ID) or incident URL (https://gitlab.com/OWNER/REPO/-/issues/incident/ID).

If a non-incident ID/URL is used in the incident view command, it responds with an error. incident view is intended to display incidents only, whereas issue view can display issues of any type: issues, incidents, etc.

Related Issues

Resolves #1189 (closed)

Contributes to &9586

How has this been tested?

With the following commands:

• glab incident show <INCIDENT_ID>
• glab incident show <INCIDENT_URL>
• glab incident show <ISSUE_URL>
• glab incident show <INCIDENT_ID> --comments
• glab incident show <INCIDENT_ID> --web

Screenshots (if appropriate):

incident --help	incident view --help	view an incident	Hidden text*	Opening non-incident

* Needs to be fixed in a follow-up

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation
• Chore (Related to CI or Packaging to platforms)