fix: defaults for prompt from flags then options

[lkingland]

• 🐛 select prompt option based on flag or default

Fixes #819
Fixes #820

Related issue #814

/kind bug

Fix a bug where interactive prompt defaults were not being used

[knative-prow-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lkingland

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[codecov]

Codecov Report

Merging #821 (a8a79e0) into main (879031a) will decrease coverage by 0.05%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main     #821      +/-   ##
==========================================
- Coverage   42.85%   42.79%   -0.06%     
==========================================
  Files          47       47              
  Lines        4749     4755       +6     
==========================================
  Hits         2035     2035              
- Misses       2422     2428       +6     
  Partials      292      292              

Impacted Files	Coverage Δ
cmd/create.go	46.21% <ø> (ø)
cmd/invoke.go	32.36% <0.00%> (-0.14%)	⬇️
cmd/root.go	64.49% <0.00%> (-2.43%)	⬇️

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[lance]

/lgtm