feat(AWS Lambda): Support referencing images with tags

[pgrzesik]

Adds support for referencing images with tags

To also share a bit more context about it because it seems fairly simple, but there was a little bit more consideration to it. I was also wondering if we should resolve SHA for an image at all times, because it seems like ImageUri can also accept an URI with tag only. My first idea here that maybe (without versioning), if ImageUri would be e.g. xxx.xxx/repo-name:latest, then after updating the image under the latest tag in that repo will result in new Lambdas being invoked with that newly pushed image. I was a bit surprised to learn that it's not the case, it seems like Lambda internally is somehow still pinning the image to specific sha (maybe during the image optimization process that happens before the first invocation) and you have to force update your Lambda function anyway. In that case, I feel like, at this point, we should always resolve the specific SHA of an image.

Closes: #8621

[codecov]

Codecov Report

Merging #8683 (4b71b1c) into master (ef53050) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #8683      +/-   ##
==========================================
+ Coverage   87.23%   87.25%   +0.01%     
==========================================
  Files         255      255              
  Lines        9597     9611      +14     
==========================================
+ Hits         8372     8386      +14     
  Misses       1225     1225              

Impacted Files	Coverage Δ
lib/plugins/aws/provider.js	93.06% <ø> (ø)
lib/plugins/aws/package/compile/functions.js	96.18% <100.00%> (+0.19%)	⬆️

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[medikoo]

I feel like, at this point, we should always resolve the specific SHA of an image.

Thanks for elaborating on that. I had exactly same thought path which lead me to assumption that we always should put SHA in CF config. I should have shared that in original issue.

Great work @pgrzesik, I have nothing to add!