strapi-plugin-upload: Read responsive breakpoints from config

[blefevre]

What does it do?

This PR changes the upload plugin to read the responsive image breakpoints from the config instead of being hardcoded.
The hardcoded values are still available as defaults if the config is not present.

Why is it needed?

Currently adjusting the sizing or names of the responsive images requires overriding the entire image-manipulation.js file, which is prone to errors and breaking when upgrading.

[strapi-cla]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #9002 (739914d) into master (7e0d50c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #9002   +/-   ##
=======================================
  Coverage   34.65%   34.65%           
=======================================
  Files        1308     1308           
  Lines       14452    14452           
  Branches     1438     1438           
=======================================
  Hits         5008     5008           
  Misses       8529     8529           
  Partials      915      915           

Flag	Coverage Δ
front	26.02% <ø> (ø)
unit	54.92% <ø> (ø)

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[alexandrebodin]

Hi @blefevre thank you fro this PR :) I'm happy to move forward with it but you will need to update our doc so people can find the option :) Go over to our doc repo https://github.com/strapi/documentation ;)
If you need any help @derrickmehaffy is the person to talk to ;)

[derrickmehaffy]

Hi @blefevre thank you fro this PR :) I'm happy to move forward with it but you will need to update our doc so people can find the option :) Go over to our doc repo https://github.com/strapi/documentation ;)
If you need any help @derrickmehaffy is the person to talk to ;)

Would be happy to help if you have questions about the documentation.

[blefevre]

Documentation PR created here: strapi/documentation#88

[blefevre]

There was some sort of issue with the tests, I've rebased onto master and it seems okay now.

[alexandrebodin]

LGTM. Nice addition :D

[derrickmehaffy]

This pull request has been mentioned on Strapi Community Forum. There might be relevant details there:

https://forum.strapi.io/t/new-release-strapi-v3-4-6/2631/1