Run Gemnasium on file matches in all directories

What does this MR do and why?

Describe in detail what your merge request does and why.

This MR modifies the default Dependency Scanning templates to search all directories for supported files. This will allow for setting DS_MAX_DEPTH which is a variable to be introduced in this MR: gitlab-org/security-products/analyzers/gemnasium!441 (merged)

Related Issue: Limit directory depth of Gemnasium scans (#292455 - closed)

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