Allow the name/version@user/channel reference format

[anders-zpt]

Problem:
With the switch from output parsing to reading the JSON file, the support for Conan 1.x style package references was dropped.

Solution:
This PR re-adds support for parsing out the user and channel fields from a Conan 1.x style package reference and formats the Artifactory URL with these values. It reuses the ParsePackageReference function already in the repo.

• All tests passed. If this feature is not already covered by the tests, I added new tests.
• All static analysis checks passed.
• Appropriate label is added to auto generate release notes.
• I used gofmt for formatting the code before submitting the pull request.
• PR description is clear and concise, and it includes the proposed solution/fix.

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[reshmifrog]

We do not support conan 1.x so this is redundant, We have only added support for conan 2.x.

[anders-zpt]

This PR is not about Conan 1.x support in general. It's just about supporting the format user/version@name/channel. I'm happy to change the PR title

[anders-zpt]

@reshmifrog we still have a lot of packages in the old format and won't be able to use the jf conan command until a fix like this is merged.