fix(modal): focus modal container on init

[IlyaSurmay]

Fixes #3356

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[codecov]

Codecov Report

Merging #3357 into development will decrease coverage by 0.02%.
The diff coverage is 0%.

@@              Coverage Diff               @@
##           development   #3357      +/-   ##
==============================================
- Coverage        65.03%     65%   -0.03%     
==============================================
  Files              210     210              
  Lines             5691    5693       +2     
  Branches          1000    1001       +1     
==============================================
  Hits              3701    3701              
- Misses            1724    1726       +2     
  Partials           266     266

Impacted Files	Coverage Δ
src/modal/modal-container.component.ts	19.29% <0%> (-0.71%)	⬇️

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