refactor(commands/completion): always default to bash

[maxice8]

No description provided.

[codecov]

Codecov Report

Merging #507 (da5218d) into trunk (41720e8) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##            trunk     #507   +/-   ##
=======================================
  Coverage   57.80%   57.81%           
=======================================
  Files          83       83           
  Lines        5565     5561    -4     
=======================================
- Hits         3217     3215    -2     
+ Misses       2017     2016    -1     
+ Partials      331      330    -1     

Impacted Files	Coverage Δ
commands/completion/completion.go	100.00% <100.00%> (+6.06%)	⬆️

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[profclems]

Thanks for taking this on!

It is right we default to bash if no shell is specified. We should add the to the --shell flag usage info that default is bash. Since cobra already prints the default value if set, we should set the default value to bash:

	completionCmd.Flags().StringVarP(&shellType, "shell", "s", "bash", "Shell type: {bash|zsh|fish|powershell}")

[maxice8]

Thanks for looking at it, I set bash as default outright and removed all the code that deals with the value being empty