Add CardsV2 Support to Google Chat

[tpaulus]

This change adds support for Googles new CardSV2 format which replaces the now deprecated V1 format. The Google Generated shapes are now used for Message parsing to ensure complete coverage and accuracy between the docs and what the Google APIs expect.

Added unit tests and update docs to reflect these changes.

Fixes #158

[codecov]

Codecov Report

Patch coverage: 64.70% and project coverage change: +0.13% 🎉

Comparison is base (e80a8e9) 53.80% compared to head (32e9413) 53.93%.
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #201      +/-   ##
==========================================
+ Coverage   53.80%   53.93%   +0.13%     
==========================================
  Files          35       35              
  Lines        3249     3278      +29     
==========================================
+ Hits         1748     1768      +20     
- Misses       1244     1250       +6     
- Partials      257      260       +3     

Files Changed	Coverage Δ
pkg/services/googlechat.go	61.36% <64.70%> (+2.14%)	⬆️

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[pims]

@zachaller @mayzhang2000 would one of you be able to dedicate some time to reviewing this PR in the near future?
The desired end goal is to have this functionality available in the next realease of argo-rollouts.

We’ve been running with this patch for a while now and it's working very well.

Thank you 🙏

[pasha-codefresh]

@tpaulus could you please fix conflicts, also WDYT about support of two versions? ( v1 and v2 ).

[tpaulus]

PR has been rebased against master.

As for how V1 and V2 support works, there is a new Struct called cardsV2 which exposes the new shapes, while the original cards interface remains the same. The change is backwards compatible, while still enabling the new card items, which cannot be translated to the new interface because there is little to no overlap between V1 and V2 modules (thanks Google).

[pasha-codefresh]

Yeah, but once people update notification engine in their argocd instances, their notifications will stop work until they migrate to new templating and so on

[tpaulus]

I'm not sure I follow, the V1 interface is still supported by the integration and nothing changed with the shape of the V1 integration other than using the Google Protobuffs for the notification, which are the same as what was previously there. The TestCardMessage_GoogleChat Unit Test shows that this still works, as the input remains unchanged.

[pasha-codefresh]

Get it, @tpaulus , i will review it tomorrow and will back to you

[pasha-codefresh]

Great job @tpaulus , thanks