🐛 [RUMF-791] prevent IE11 performance entry error

[bcaudan]

Motivation

toJSON is not available in IE11, prevent execution error

Changes

check if toJSON available before using it

Testing

manual

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I have gone over the contributing documentation.

[codecov-io]

Codecov Report

Merging #633 (092dbb7) into master (a5c6271) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #633      +/-   ##
==========================================
+ Coverage   87.76%   87.78%   +0.01%     
==========================================
  Files          56       56              
  Lines        2575     2578       +3     
  Branches      555      556       +1     
==========================================
+ Hits         2260     2263       +3     
  Misses        315      315              

Impacted Files	Coverage Δ
...rumEventsCollection/resource/matchRequestTiming.ts	95.00% <100.00%> (+0.88%)	⬆️

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