Remove product synchronization duplication

[maximenoel8]

What does this PR change?

In BV, we are currently synchronizing twice slemicro 5.5 causing issue.
Remove the 5.5 synchronization to only get the product during proxy tag.
I choose to keep proxy because I think there is an issue for MU pipeline and we will always have proxy for the deployment but not necessary slemiro5.5 client.
The client will be cover by proxy

GUI diff

No difference.

• DONE

Documentation

• No documentation needed: only internal and user invisible changes

• DONE

Test coverage

ℹ️ If a major new functionality is added, it is strongly recommended that tests for the new functionality are added to the Cucumber test suite

• No tests: already covered

• DONE

Links

Issue(s): #
Port(s): https://github.com/SUSE/spacewalk/pull/26295

• DONE

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[srbarrios]

Another option is to add a tag on top of this scenario, to skip if the proxy exist.

But I'm gonna approve it, because this solution works too.