Remove generate-gitops warning about categories

[sgress454]

Related issue: Resolves #30453

All the work for this was already done in #32492. I verified that generate-gitops outputs the expected categories, and that gitops reads them back in correctly. This PR just removes the warning

[claude]

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[Copilot]

Pull request overview

Removes an outdated generate-gitops warning about software categories now that categories are supported end-to-end (implemented previously in #32492), aligning CLI output with current GitOps behavior.

Changes:

• Delete the “Software categories are not supported by this tool yet…” note emitted by fleetctl generate-gitops for non-global runs.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 66.62%. Comparing base (f7f5664) to head (5cb505b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #42514      +/-   ##
==========================================
- Coverage   66.63%   66.62%   -0.01%     
==========================================
  Files        2532     2532              
  Lines      202555   202579      +24     
  Branches     9180     9180              
==========================================
+ Hits       134968   134973       +5     
- Misses      55384    55400      +16     
- Partials    12203    12206       +3     

Flag	Coverage Δ
backend	68.46% <ø> (-0.01%)	⬇️

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