Draft: Enable rust sast scan

What does this MR do and why?

Updates SAST.gitlab-ci.yml and SAST.latest.gitlab-ci.yml to trigger the semgrep-sast job when Rust (*.rs) files are detected.

What are the relevant issue numbers?

• Support Rust SAST Analyzer (#390733)
• Enable Support for Rust in Semgrep Analyzer (#439046 - closed)

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