fix(lambda-at-edge): add retries for s3 calls

[dphang]

Updates s3-client v3 and adds retries to fix: aws/aws-sdk-js-v3#1196

[codecov]

Codecov Report

Merging #720 into master will decrease coverage by 0.13%.
The diff coverage is 55.55%.

@@            Coverage Diff             @@
##           master     #720      +/-   ##
==========================================
- Coverage   79.80%   79.67%   -0.14%     
==========================================
  Files          55       55              
  Lines        1763     1771       +8     
  Branches      378      380       +2     
==========================================
+ Hits         1407     1411       +4     
- Misses        298      302       +4     
  Partials       58       58              

Impacted Files	Coverage Δ
...ackages/libs/lambda-at-edge/src/default-handler.ts	93.05% <55.55%> (-1.38%)	⬇️

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