fix(Modal): remove dimmer={false}

[mihai-dinculescu]

Fixes #2873.

In fact, this change should be done in v0.81.0 when we performed update to SUI 2.3 (#2657). Without a dimmer, it is no longer able to figure out the position of the modal.

A Special Message about Flex Modals

There will be an update shortly to resolve issues related to flex modals when using multiple modals and detachable: false, in order to not hold up this release, we've decided to move forward without a fix.

A general solution will most likely require branching code for IE11 which will disable flex (as IE11 doesnt correctly implement the latest spec for absolute positioned flex containers).

Before

You able to hide a dimmer with: <Modal dimmer={false} />.

After

This behaviour is deprecated and removed, you need to apply custom styling for dimmers if you actually need this feature.

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Changes

1. Multiple example

Remove the now controversial dimmer={false}. It adds nothing to the example anyway.

2. Close Config example

Make it so that the "Yes" and "No" buttons inside the Modal can close it. The "No Close on Dimmer Click" example is currently unclosable and requires browser refresh.

3. Dimmer examples

Removed useless example with dimmer={false}.

4. Remove useless tests and update propTypes for the dimmer prop

[codecov-io]

Codecov Report

Merging #2882 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #2882   +/-   ##
=======================================
  Coverage   99.67%   99.67%           
=======================================
  Files         161      161           
  Lines        2733     2733           
=======================================
  Hits         2724     2724           
  Misses          9        9

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

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[layershifter]

@mihai-dinculescu thanks for PR 👍 I've pushed some updates and update the PR's description

[mihai-dinculescu]

Whops. It was already done. Sorry about that.

[levithomason]

I believe this is actually a bug fix to 0.80.1, correct? It should have been shipped as a breaking change in the 0.81.0 release, but now that we've missed that I am inclined to say we're "fixing" the 0.81 release.

Is this sane to others?

[layershifter]

In fact, dimmer={false} already is not working, so we can ship this as a fix. I updated title 👍

[layershifter]

Performed a review again, merged. @mihai-dinculescu thanks 👍

[levithomason]

Released in semantic-ui-react@0.81.2.