fix: add a better workaround for iron-list scrollToIndex issue

[tomivirkki]

A change in a previous PR affected how the iron-list issue mentioned here manifests. Needed to improve the workaround to mitigate the issue with the changed setup. The regression was caught by a GridPro Flow-component integration test.

[sonarcloud]

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0 Bugs
0 Vulnerabilities
0 Security Hotspots
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No Coverage information
0.0% Duplication

[vaadin-bot]

Hi @tomivirkki , this commit cannot be picked to 21.0 by this bot, can you take a look and pick it manually?
Error Message: Error: Command failed: git cherry-pick 19b1d54
warning: inexact rename detection was skipped due to too many files.
warning: you may want to set your merge.renamelimit variable to at least 3756 and retry the command.
error: could not apply 19b1d54... fix: workaround scrollToIndex issue (#2922)
hint: after resolving the conflicts, mark the corrected paths
hint: with 'git add ' or 'git rm '
hint: and commit the result with 'git commit'

[vaadin-bot]

This ticket/PR has been released with platform 22.0.0.beta1 and is also targeting the upcoming stable 22.0.0 version.