fix(Modal): prevent resize loop for full screen height

[marcdavi-es]

This fixes the bug reported here.

My assumptions:

1. It is a good thing to allow consumers of Modal to override the full screen modal to fill the height of the screen.
2. The change does not materially affect the existing functionality. The scrolling class will continue to be set on modals which are larger than window.innerHeight.

[welcome]

💖 Thanks for opening this pull request! 💖

Here is a list of things that will help get it across the finish line:

• Run yarn lint locally to catch formatting errors. This will fix some errors automatically, commit and push any changes.
• Run yarn test locally to catch errors. This ensures all components still behave as they should.
• Run yarn start to run the doc site locally and try a few pages, ensuring everything is in good working order.
• Include tests when adding/changing behavior.

We get a lot of pull requests on this repo, so please be patient and we will get back to you as soon as we can.

[codecov-io]

Codecov Report

Merging #3024 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #3024      +/-   ##
==========================================
+ Coverage   99.96%   99.96%   +<.01%     
==========================================
  Files         163      163              
  Lines        2738     2743       +5     
==========================================
+ Hits         2737     2742       +5     
  Misses          1        1

Impacted Files	Coverage Δ
src/modules/Modal/Modal.js	100% <100%> (ø)	⬆️
src/modules/Popup/Popup.js	100% <0%> (ø)	⬆️
src/modules/Rating/RatingIcon.js	100% <0%> (ø)	⬆️

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[levithomason]

This is great, thanks! Let's fix the test which is currently too loose:

Semantic-UI-React/test/specs/modules/Modal/Modal-test.js

Line 489 in 55f4c25

it('adds the scrolling class to the body when taller than the window', (done) => {

Perhaps we can split this into two tests. One that it('does not add the scrolling class to the body when equal to the window height') and leave the current test. This new test could set an inline style on the Modal to match the window height that is already set in the test.

This way, we are sure this works as expected.

[marcdavi-es]

@levithomason thanks, that's done :)

[welcome]

Congrats on merging your first pull request! 🎉🎉🎉