a tool to fetch plugin sources from the 3+ upstream repos (b/b, bcp, roadiehq?, rhdh-plugins, janus-idp/backstage-plugins) - new sync-midstream.sh script 

GL repo format should look like this:

/overlay-repo/<content of the overlay-repo>
/workspaces/backstage/<whole backstage repo content>
/workspaces/ocm/<root of community plugins repo + sparse checkout of workspaces/ocm>
/workspaces/quay/<root of community plugins repo + sparse checkout of workspaces/quay>

Steps:

• clone https://github.com/davidfestal/rhdh-dynamic-plugin-export-overlays from a specific branch into GL repo
• then use instructions in that repo to fetch more content by repo + digest + path into /workspaces/
• then transform:
  • To improve performance we can strip out the postinstall command from the workspace root package.json files so that we don't need to include workspaces/repo-tools/ and all the bcp repo root files copied over for every workspace.

Once that's done we can run the export command from https://github.com/davidfestal/rhdh-plugin-export-utils/blob/multi-plugins-repo/export-dynamic/export-dynamic.sh

See parent issue RHIDP-2449. Continued in RHIDP-2450 once we have the repo populated. 

This will live in https://gitlab.cee.redhat.com/rhidp/rhdh-plugin-catalog and borrow heavily from https://gitlab.cee.redhat.com/rhidp/rhdh 

TODOs:

• get RHD version of davidfestal/rhdh-plugin-export-utils into sync-midstream.sh
• get RHD version of davidfestal/rhdh-dynamic-plugin-export-overlays into upstream_repos.yml
  • include more than b/b and quay and ocm packages
• run sync-midstream.sh to pull latest content

• wrap export-dynamic.sh in tkn task and enable in new application/component/pipeline - RHIDP-5415
• figure out how to use the same pipeline to release 1 or more changed plugins (not all of them every time)

• Exclude most of the community plugins when sync-midstream.sh fires that won’t be included downstream
  • include/exclude regexps
  • Exclude entire workspaces
  • Exclude plugins within a workspace (b/b)