Issue number: resolves#28102
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## What is the current behavior?
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When one modal is added and another modal is removed, the modal that is
removed does not account for the newly added modal when updating the
overlay context in React. As a result, the inner contents of the newly
added modal is not mounted.
We originally tried to fix this in
https://github.com/ionic-team/ionic-framework/pull/24553, but the fix
was not complete. While storing the latest information in a React ref
was correct, the way we updated the ref was done in a way such that data
was still stale.
In particular, the `overlaysRef` is updated whenever `IonOverlayManager`
is re-rendered. State updates are batched, so updating the state twice
in quick succession does not necessarily result in 2 separate renders.
## What is the new behavior?
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this PR. -->
- We need to make sure the ref is updated synchronously before any
render so that `addOverlay` and `removeOverlay` always have access to
the latest data.
- Added a test
## Does this introduce a breaking change?
- [ ] Yes
- [x] No
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and migration path for existing applications below. -->
## Other information
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screenshots of how the component looks before and after the change. -->
Dev build: `7.3.3-dev.11693592339.18e000af`
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Co-authored-by: Maria Hutt <thetaPC@users.noreply.github.com>
Co-authored-by: Amanda Johnston <90629384+amandaejohnston@users.noreply.github.com>
