Implement multi tag for build

[ulyssessouza]

Add multitag support for build

Note that with this implementation, building multiple times with different tags and building just one with multiple tags doesn't produce the same output. Check this:

- What I did Added the option to use multiple tags to an app image

- How I did it By turning the tag option into a list

- How to verify it

$ docker app build -t hello:v1 -t hello:v2 example/hello-world

- Description for the changelog Add multitag support for build

- A picture of a cute animal (not mandatory)

[silvin-lubecki]

You have different IDs as we now insert the build time into the bundle.json... So the digest will differ each time you build.

[ulyssessouza]

@silvin-lubecki Yep! And I think that's strange/inconsistent. Makes me feel that this kind of info would be better outside of the bundle.json.

[codecov[bot]]

Codecov Report

Merging #771 into master will not change coverage. The diff coverage is n/a.

@@          Coverage Diff           @@
##           master    #771   +/-   ##
======================================
  Coverage    71.1%   71.1%           
======================================
  Files          67      67           
  Lines        3835    3835           
======================================
  Hits         2727    2727           
  Misses        756     756           
  Partials      352     352

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