feat: Add Sources tab to show all sources of a multi-source app (#17274)

[keithchong]

Fixes #17274

The original Multi-Source enhancement PR supported viewing only the first source of a multi-source application. The parameters were not editable either.

This PR adds a bit more support in that it will show all the sources of the multi-source application under a new Sources tab (which replaces the Parameters tab). Arguably, these changes could have been part of the original PR. The parameters are still read-only. (Making the input/parameters editable will be part of another PR.)

Note: There is effectively no change in behaviour for applications that still use the single source. The repo URL, path and related inputs are still shown in the Summary tab. When the source field is deprecated and removed, the corresponding code should be updated.

This is just the first stage from the design proposal.

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this does not need to be in the release notes.
• The title of the PR states what changed and the related issues number (used for the release note).
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 49.55%. Comparing base (f87897c) to head (f2db50e).
Report is 54 commits behind head on master.

❗ Current head f2db50e differs from pull request most recent head 42a8a83. Consider uploading reports for the commit 42a8a83 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #17275      +/-   ##
==========================================
- Coverage   49.73%   49.55%   -0.18%     
==========================================
  Files         274      273       -1     
  Lines       48948    48288     -660     
==========================================
- Hits        24343    23928     -415     
+ Misses      22230    21998     -232     
+ Partials     2375     2362      -13     

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[agaudreault]

LGTM. but a review from a "UI" folk/maintainer would be good to have!

[ishitasequeira]

Thanks @keithchong. The PR looks great!! I just have a few comments.

[ishitasequeira]

Thanks @keithchong! The PR LGTM 🚀