Fix PixiJS v5 compatibility issues

[michalochman]

Fixes #118

[codecov]

Codecov Report

Merging #123 into master will decrease coverage by 1.14%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master     #123      +/-   ##
==========================================
- Coverage   95.72%   94.58%   -1.15%     
==========================================
  Files          11       11              
  Lines         234      240       +6     
==========================================
+ Hits          224      227       +3     
- Misses         10       13       +3

Impacted Files	Coverage Δ
src/ReactPixiFiber.js	96.73% <66.66%> (-3.27%)	⬇️

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