fix(Select): enforce content update after render

[Lodin]

Fixes #148.

Also this PR simplifies the testing approach (only for Select component) to avoid weird failures.

[Lodin]

@vursen, is this expression expected to work?

render(<Select renderer={Renderer} value="bar" />);
expect(document.querySelector('vaadin-select-value-button')).to.have.text('Bar');

render(<Select renderer={Renderer} value="foo" />);
expect(document.querySelector('vaadin-select-value-button')).to.have.text('Foo');

[vursen]

is this expression expected to work?

I believe so, unless React renders this asynchronously.

[codecov-commenter]

Codecov Report

Attention: 2 lines in your changes are missing coverage. Please review.

Comparison is base (e131230) 99.36% compared to head (fa15b6a) 98.22%.

Files	Patch %	Lines
src/utils/useMergedRefs.ts	66.66%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #156      +/-   ##
==========================================
- Coverage   99.36%   98.22%   -1.15%     
==========================================
  Files          24       25       +1     
  Lines         158      169      +11     
  Branches       13       16       +3     
==========================================
+ Hits          157      166       +9     
- Misses          0        1       +1     
- Partials        1        2       +1     

Flag	Coverage Δ
unittests	98.22% <81.81%> (-1.15%)	⬇️

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[vursen]

Were these SideNav exports intentionally included in this PR? Looks like an unrelated change.

[Lodin]

🤔

[Lodin]

I guess, it was done by a script, because we already have SideNav on line 421, but no supporting export on 538. I would suggest to leave it here because we would need to include it anyway (and probably it's gonna be generated on each script run).