fix: Could not update application spec: could not find an image-tag annotation for image

[chengfang]

Fixes https://github.com/argoproj-labs/argocd-image-updater/issues/840

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 77.77778% with 2 lines in your changes missing coverage. Please review.

Project coverage is 73.50%. Comparing base (5990a9b) to head (25d55fa). Report is 114 commits behind head on master.

Files with missing lines	Patch %	Lines
pkg/argocd/update.go	77.77%	1 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #843      +/-   ##
==========================================
+ Coverage   73.48%   73.50%   +0.01%     
==========================================
  Files          31       31              
  Lines        3142     3144       +2     
==========================================
+ Hits         2309     2311       +2     
  Misses        695      695              
  Partials      138      138              

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[jannfis]

@chengfang can you please resolve the conflict?