Replace a modal resize hack with usage of the action-menu store.

[codyrancher]

Summary

Note: this is for 2.14.

Fixes #10559

Technical notes summary

We were hackily modifying the width of a modal dialog. This uses our existing action-menu store responsible for managing the state of the modals to update the width of the modal which is already reactive.

Areas or cases that should be tested

WorkloadRollbackDialog when switching toggling between show/hide diff.

Areas which could experience regressions

WorkloadRollbackDialog when switching toggling between show/hide diff.

Screenshot/Video

sizedialog.mp4

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[codyrancher]

We want to modify properties instead of assign a full new object to modalData because it can trigger a full re-render of a modal which can reset component state unintentionally.

[rak-phillip]

LGTM