chore: Cleanup SAST report fixtures

What does this MR do?

Updates very outdated gl-sast-report.json fixtures

The report fixtures we use within the rails application are very old. They do not test real-world conditions and have a high likelihood of hiding bugs.

• Updates gl-sast-report.json from v1.2 to v14.0.0.
• Removes mixed finding types (bandit, flawfinder, find-sec-bugs => find-sec-bugs)
• Updates tests that relied on previous fixed values and counts

Relates #326511 (closed)

Does this MR meet the acceptance criteria?

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