PortAddonPullRequest: reduce noise by filtering PRs to port

[sebalix]

Address issue #21

PRs that are updating both the analyzed module + other ones (here called 'satellite') were listed by oca-port, even if the commits related to the analyzed module were already ported, because contributions on these satellite modules were not (yet) ported.

In the context of the analyzed module, this brings noise and such PR should not be proposed to be ported, but only mentioned.

There are now two kinds of detected PRs:

• the ones that are updating the current analyzed module: they are proposed to the user as "to be ported" as usual
• the ones where only satellite modules/files remain to be ported: such modules are now listed (in verbose mode), and the user invited to run oca-port on them.

As such PRs with commits updating only satellite modules are not proposed anymore to the user, some modules will now be considered as "Fully ported" instead of still having some "Commits to port", which is accurate from a reporting POV 🎉

Example of interactive output on shopfloor_mobile from OCA/wms:

Example of JSON output on stock_storage_type from OCA/wms:
$ oca-port origin/14.0 origin/16.0 stock_storage_type --verbose --dry-run --output=json | jq .
Before

{
  "process": "port_commits",
  "results": {
    "258": {
      "url": "https://github.com/OCA/wms/pull/258",
      "ref": "OCA/wms#258",
      "author": "sebalix",
      "title": "[13.0->14.0][oca-port-pr-#58] Add stock_storage_type_buffer",
      "merged_at": "2021-08-04T10:25:21Z",
      "missing_commits": [
        "642de1b44a5789900ee42cccb58bd3dd29451cdd",
        "dc09fb6f2834059e05bc3de9377204d589fc3ad8",
        "7775e31b8e6ec7a5dd48a0c081cd429375b9b89e"
      ]
    }
  }
}

After

{}  # Now considered as "Fully ported"

Still in OCA/wms repository, for shopfloor module this reduces the number of PRs to port from 34 to 11.

TODO

• fix & add tests