fix(aws-cloudfront, nextjs-component): fix aliases updating when domain is used

[dphang]

• When domain is used, it should completely manage all aliases attached to CloudFront distribution instead of trying to push onto existing aliases set. Otherwise, there could be strange behavior when it's manually updated and/or domains are changed.
• aliases input in cloudfront can be used if additional aliases apart from domain name are needed (and domain likely should be managed externally instead, as this is a more complex use case).

[codecov]

Codecov Report

Merging #731 into master will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #731   +/-   ##
=======================================
  Coverage   79.69%   79.69%           
=======================================
  Files          55       55           
  Lines        1798     1798           
  Branches      390      390           
=======================================
  Hits         1433     1433           
  Misses        307      307           
  Partials       58       58           

Impacted Files	Coverage Δ
packages/serverless-components/domain/utils.js	0.00% <0.00%> (ø)

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