Fix race condition in image annotations loading and drawing them on the canvas

[scottbell]

Closes #6749

Describe your changes:

Fixes race condition between loading the image annotations and drawing them on canvas.

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Author Checklist

• Changes address original issue?
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• Has this been smoke tested?
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Reviewer Checklist

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[deploysentinel]

Current Playwright Test Results Summary

✅ 13 Passing

Run may still be in progress, this comment will be updated as current testing workflow or job completes...

(Last updated on 06/21/2023 06:11:03pm UTC)

Run Details

Running Workflow e2e-couchdb on Github Actions

Commit: 437310d

Started: 06/21/2023 06:09:28pm UTC

View Detailed Build Results

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[codecov]

Codecov Report

Merging #6751 (f7df3ab) into master (f254d4f) will increase coverage by 0.10%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #6751      +/-   ##
==========================================
+ Coverage   53.79%   53.89%   +0.10%     
==========================================
  Files         624      624              
  Lines       24847    24848       +1     
  Branches     2493     2493              
==========================================
+ Hits        13366    13393      +27     
+ Misses      10813    10788      -25     
+ Partials      668      667       -1     

Flag	Coverage Δ		*Carryforward flag
e2e-full	42.14% <ø> (ø)		Carriedforward from 03a9309
e2e-stable	55.25% <ø> (-0.30%)	⬇️
unit	48.66% <0.00%> (+0.17%)	⬆️

*This pull request uses carry forward flags. Click here to find out more.

Impacted Files	Coverage Δ
...c/plugins/imagery/components/AnnotationsCanvas.vue	2.63% <0.00%> (-0.02%)	⬇️

... and 13 files with indirect coverage changes

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[ozyx]

LGTM! Tested locally and seems to work well