Add linting workflows

[fgrosse]

• Add Go module caching to CI workflow
• Add workflow to lint the source code
• Add shellcheck linter

[github-advanced-security]

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[github-actions]

Merging this branch will not change overall coverage

Impacted Packages	Coverage Δ	🤖

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Coverage by file

Changed File	Coverage Δ	Total	Covered	Missed	🤖

Please note that the "Total", "Covered", and "Missed" counts above refer to code statements instead of lines of code. The value in brackets refers to the test coverage of that file in the old version of the code.