Ptest Fix for package conda

[sameluch]

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• [x] The toolchain has been rebuilt successfully (or no changes were made to it)
• [x] The toolchain/worker package manifests are up-to-date
• [x] Any updated packages successfully build (or no packages were changed)
• [x] Packages depending on static components modified in this PR (Golang, *-static subpackages, etc.) have had their Release tag incremented.
• [x] Package tests (%check section) have been verified with RUN_CHECK=y for existing SPEC files, or added to new SPEC files
• [x] All package sources are available
• [x] cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• [x] LICENSE-MAP files are up-to-date (./SPECS/LICENSES-AND-NOTICES/data/licenses.json, ./SPECS/LICENSES-AND-NOTICES/LICENSES-MAP.md, ./SPECS/LICENSES-AND-NOTICES/LICENSE-EXCEPTIONS.PHOTON)
• [x] All source files have up-to-date hashes in the *.signatures.json files
• [x] sudo make go-tidy-all and sudo make go-test-coverage pass
• [x] Documentation has been updated to match any changes to the build system
• [x] If you are adding/removing a .spec file that has multiple-versions supported, please add @microsoft/cbl-mariner-multi-package-reviewers team as reviewer (Eg. golang has 2 versions 1.18, 1.21+)
• [x] Ready to merge

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Summary

What does the PR accomplish, why was it needed? The ptest for conda has been failing due to dependency issues. Additionally, some test can be skipped for the lack of an external conda package, conda_libmamba_solver, which we don't ship so these tests must be skipped.

Change Log

• Add missing dependencies via pip install and BuildRequires
• Add skips for tests using conda_libmamba_solver

Does this affect the toolchain?

NO

Test Methodology

• Buddy Build: https://dev.azure.com/mariner-org/mariner/_build/results?buildId=588908&view=results