Add QA scripts for job integration tests

Add Ruby, RSpec-based scripts in order to replace the compare_reports.sh Shell script.

Tested in gitlab-org/security-products/tests/go-modules!67 (closed)

See gitlab-org/gitlab#299038 (closed)

% docker run -ti --rm -v $PWD/../gemnasium/qa/expect/go-modules:/app -w /app integration-test:qa-scripts
/app # export DS_REPORT_URL=https://gitlab.com/gitlab-org/security-products/analyzers/gemnasium/-/raw/master/qa/expect/go-modules/gl-dependency-scanning-report.json
/app # dependency-scanning-qa gl-dependency-scanning-report.json
......

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6 examples, 0 failures