Add dimensions for images

[yvmarques]

By default Drupal doesn't provide dimensions for files entities. This information is saved at the field level. In order to have dimensions when we request derivatives, we need to get those values to fill the height and width for a given image like this we will get the calculated dimensions for the style requested.

[codecov]

Codecov Report

Merging #938 into 8.x-4.x will decrease coverage by 0.09%.
The diff coverage is 55.55%.

@@             Coverage Diff              @@
##             8.x-4.x     #938     +/-   ##
============================================
- Coverage      61.91%   61.81%   -0.1%     
- Complexity       675      678      +3     
============================================
  Files             95       95             
  Lines           1402     1409      +7     
============================================
+ Hits             868      871      +3     
- Misses           534      538      +4

Impacted Files	Coverage Δ	Complexity Δ
...taProducer/Entity/Fields/Image/ImageDerivative.php	76.19% <55.55%> (-16.67%)	7 <0> (+3)

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[fubhy]

Thanks!