Fix packager reported by Gemnasium for Gradle and Pipenv projects

What does this MR do and why?

• Fix package manager reported by gemnasium-maven for Gradle projects.
• Fix package manager reported by gemnasium-python for Pipenv and Setuptools projects.
• Properly present the newly introduced package managers in the Dependency List.
• Support the newly introduced package managers in the Dependencies API, as filters.
• Fix a bug in the Dependencies API: the packager_manager param was compared as a String, not as an Array. As a result, pipenv matched pip, because the former "includes" the latter. This bug was harmless before introducing pipenv.
• Remove TableSyntax from spec, because this was not needed.
• Add a spec for when the package_manager param is an Array, and not a String.

Testing

Changes to the CI templates are tested using the Secure test projects:

• In gitlab-org/security-products/tests/python-pipenv!66 (closed), the report now sets the package_manager to pipenv.
• In gitlab-org/security-products/tests/java-gradle!69 (closed), the report now sets the package_manager to gradle.

There's no test project for Setuptools.

Screenshots or screen recordings

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #338252 (closed)