Rename command list with ls

[ulyssessouza]

- What I did
Rename command list with ls

- How I did it
Rename command list with ls and added an alias to list

- How to verify it
docker app ls
docker app list
docker app --help

- Description for the changelog
Rename command list with ls

- A picture of a cute animal (not mandatory but encouraged)

[codecov]

Codecov Report

Merging #636 into master will decrease coverage by 0.5%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #636      +/-   ##
==========================================
- Coverage   72.46%   71.95%   -0.51%     
==========================================
  Files          49       49              
  Lines        2600     2560      -40     
==========================================
- Hits         1884     1842      -42     
- Misses        484      486       +2     
  Partials      232      232

Impacted Files	Coverage Δ
internal/commands/list.go	84.12% <100%> (ø)	⬆️
internal/packager/init.go	60.97% <0%> (-7.38%)	⬇️
internal/commands/init.go	88.23% <0%> (-7.22%)	⬇️
types/parameters/parameters.go	92.06% <0%> (-4.77%)	⬇️

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[silvin-lubecki]

LGTM