Remove pipeline id from dismissal event in pipeline modal

Context

When a user dismisses a finding in the pipeline security tab, the modal contains the text Dismissed on pipeline #.

If the finding exists as a vulnerability in the default branch, the dismissal information for the same item does not include the pipeline number:

While working on Populate missing pipeline info for security fin... (#391402 - closed) (part of Deprecate Vulnerabilities::Feedback (&5629 - closed)), the engineer highlighted that keeping this information in the new implementation is a large effort.

Proposal

Remove the pipeline information from the modal, and replace it with the same message from the vulnerability page:

• Current: Dismissed on pipeline #793403181 at GitLab-examples / security / security-reports
• Proposed: Thiago Figueiró @thiagocsf changed vulnerability status to dismissed just now

Rationale

1. Unblock Deprecate Vulnerabilities::Feedback (&5629 - closed)
2. The information about which pipeline the user clicked "dismiss" on isn't relevant from a vulnerability management workflow perspective
3. Make the pipeline modal more consistent with the vulnerability page (i.e. vulnerability report)