Move from template analyser to psrule for security audits

[tonybaloney]

This replaces the MSDO/template analyser tool with PSRule and adds a specific main.test.bicep file with the specific configuration we want to validate.

Overall, it reduces false positives but means if we add features like private networking as optional you can test that specific profile.

[github-advanced-security]

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[tonybaloney]

Reduces the number of issues from 38 to 22. Will address those 22 in separate PRs once this is merged.