chore(TransitionablePortal): remove usage of UNSAFE_* methods

[layershifter]

Related to #3919.

Removes the usage of UNSAFE_componentWillReceiveProps for TransitionablePortal.

[codecov-commenter]

Codecov Report

Merging #3966 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #3966   +/-   ##
=======================================
  Coverage   99.84%   99.84%           
=======================================
  Files         178      178           
  Lines        3150     3152    +2     
=======================================
+ Hits         3145     3147    +2     
  Misses          5        5           

Impacted Files	Coverage Δ
...ddons/TransitionablePortal/TransitionablePortal.js	100.00% <100.00%> (ø)

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