Add a test repo to reproduce a connectivity issue

[allenporter]

Issue #225
Issue #198

Reproduces the issue with:

$ flux-local get cluster --path tests/testdata/cluster4/
NAME                                 PATH                                                              KUSTOMIZATIONS    
cluster-apps-kubernetes-dashboard    ./tests/testdata/cluster4/apps/monitoring/kubernetes-dashboard    1                 
cluster                              ./tests/testdata/cluster4/flux                                    2                 

[codecov-commenter]

Codecov Report

Merging #231 (af967a6) into main (1782ebf) will decrease coverage by 0.01%.
The diff coverage is 96.77%.

@@            Coverage Diff             @@
##             main     #231      +/-   ##
==========================================
- Coverage   91.31%   91.31%   -0.01%     
==========================================
  Files          15       15              
  Lines        1612     1635      +23     
==========================================
+ Hits         1472     1493      +21     
- Misses        140      142       +2     

Impacted Files	Coverage Δ
flux_local/git_repo.py	92.81% <96.42%> (-0.50%)	⬇️
flux_local/manifest.py	81.19% <100.00%> (+0.67%)	⬆️

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