Show only completely failed CI jobs in notifications

What does this MR do?

In chat notifications

1. Display only jobs that failed completely - even after exhausting all retries.
2. When same job failed multiple times, display only the first instance. Accessing other failed instances from the job page is pretty easy, so I don't think this should be a big issue.

Note: This is a break in existing pattern. Maybe we want to move out retried jobs to a separate section as proposed in #31322 (closed) as the next iteration

Example

Consider a pipeline in this situation - Both jobs have retry: 2 set on them. job1 failed the initial attempt and first retry, but succeeded on next retry. job2 failed all three attempts.

The notifications change this MR brings can be seen in below table

Before	After
job1 was successful in a retry, but it (the failed instances) still got listed. Also, all instances of job2 got listed	job1 is not listed since it succeeded in a retry. Only one instance of job2 failure is listed, not all the retries

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done