Improve SAST NO_DIND file detection with proper boundary conditions

What does this MR do?

Improves SAST NO_DIND file detection with proper regex word boundary conditions.

This MR fixes 2 bugs:

• word boundaries were missing in many regexes, ensuring things like deruby (totally made up language) isn't detected as "ruby"
• Fix regex for identifying c and c++ distinct from c#, which is detected by a different analyzer: https://regex101.com/r/FiENMK/1

Relates to #197958 (closed)

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Does this MR meet the acceptance criteria?

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