Update the diagrams on the concepts page to better clarify repositories are typed

[pulpbot]

Author: @gerrod3 (gerrod)

Redmine Issue: 8826, https://pulp.plan.io/issues/8826

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Follow up issue after fixing https://pulp.plan.io/issues/6990

@gerrod3 , to answer your question, I'd change diagrams as well. The clarification that you added helps, however diagrams are very misleading.
I filed that issue based on user feedback who wanted to put different content types (from different plugins) into one repo and was surprised that they couldn't and their understanding came directly from interpreting the diagrams:

    RPM and Ansible content units are created in one diagram
    in the next diagram content unit 1 and 2 are added to the same repo (even though technically it's not written that those content units are from different plugins, the previous diagram strongly suggests that)

[stale]

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