feat(tests): add full coverage for Collapse component demo

[ludmilanesvitiy]

#INFO - IMPORTANT
This PR based on #4838 and should be merged only after 4838.

PR Checklist

Before creating new PR, please take a look at checklist below to make sure that you've done everything that needs to be done before we can merge it.

• read and followed the CONTRIBUTING.md guide.
• built and tested the changes locally.
• added/updated tests.
• added/updated API documentation.
• added/updated demos.

[codecov]

Codecov Report

Merging #4847 into development will decrease coverage by 0.2%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #4847      +/-   ##
===============================================
- Coverage        75.85%   75.65%   -0.21%     
===============================================
  Files              237      237              
  Lines             7336     7336              
  Branches          1464     1464              
===============================================
- Hits              5565     5550      -15     
- Misses            1369     1376       +7     
- Partials           402      410       +8

Impacted Files	Coverage Δ
src/chronos/i18n/it.ts	71.42% <0%> (-28.58%)	⬇️
src/chronos/i18n/pl.ts	72.22% <0%> (-11.12%)	⬇️
src/chronos/i18n/sk.ts	82.97% <0%> (-8.52%)	⬇️
src/chronos/i18n/cs.ts	86.44% <0%> (-6.78%)	⬇️
src/chronos/i18n/uk.ts	78.04% <0%> (-2.44%)	⬇️

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