Add command to remove application images

[rumpl]

- What I did

Added a new comand to remove application images, example:

$ docker app image ls
REPOSITORY TAG   APP NAME
my-app     1.0.0 voting-app
my-app     1.0.1 voting-app

$ docker app image rm my-app:1.0.0 my-app:1.0.1 my-app:2.0.0
Deleted: docker.io/library/my-app:1.0.0
Deleted: docker.io/library/my-app:1.0.1
Error: no such image docker.io/library/my-app:2.0.0

$ docker app image ls
REPOSITORY TAG APP NAME

- How I did it

The image rm command only remove the bundle from the bundle store, container images are not touched

- How to verify it

Look at the e2e test to see sample usage.

- Description for the changelog New subcommand docker app image rm to remove a docker application from the local bundle store.

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

[codecov[bot]]

Codecov Report

:exclamation: No coverage uploaded for pull request base (master@98cd1c5). Click here to learn what that means. The diff coverage is 64.1%.

@@           Coverage Diff            @@
##             master    #648   +/-   ##
========================================
  Coverage          ?   71.8%           
========================================
  Files             ?      52           
  Lines             ?    2713           
  Branches          ?       0           
========================================
  Hits              ?    1948           
  Misses            ?     513           
  Partials          ?     252

Impacted Files	Coverage Δ
internal/commands/image/command.go	100% <100%> (ø)
internal/commands/image/rm.go	57.14% <57.14%> (ø)
internal/store/bundle.go	69% <71.42%> (ø)

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