fix: align the default config output

[Terryhung]

Tracking issue

Closes #3186

Why are the changes needed?

What changes were proposed in this pull request?

1. Removing Unused Fields: Remove storage.connection. This reduces clutter, making the config cleaner and easier to understand.
2. Aligning Configurations: Ensures flytectl config init and flytectl demo start produce consistent configs, simplifying setup and usage. Align the admin.endpoint: dns:///localhost:30080.

How was this patch tested?

Setup process

unit test

Screenshots

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

Related PRs

Docs link

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 36.84%. Comparing base (dcdd472) to head (1781a1b).
Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5947      +/-   ##
==========================================
- Coverage   36.84%   36.84%   -0.01%     
==========================================
  Files        1309     1309              
  Lines      130994   130989       -5     
==========================================
- Hits        48271    48263       -8     
- Misses      78533    78536       +3     
  Partials     4190     4190              

Flag	Coverage Δ
unittests-datacatalog	51.58% <ø> (ø)
unittests-flyteadmin	54.10% <ø> (ø)
unittests-flytecopilot	11.73% <ø> (ø)
unittests-flytectl	62.38% <100.00%> (-0.07%)	⬇️
unittests-flyteidl	6.92% <ø> (ø)
unittests-flyteplugins	53.64% <ø> (ø)
unittests-flytepropeller	43.02% <ø> (ø)
unittests-flytestdlib	55.41% <ø> (+0.01%)	⬆️

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