Fix handling of delete in Chrome when inline void node is selected

[clauderic]

Description
This PR fixes deletion of selected inline void nodes in Chrome. Chrome does not fire a beforeinput event when deleting backwards within an inline void node, so we need to add special logic to handle this edge-case for Chrome only.

Both Firefox and Safari do not exhibit this behaviour, and fire the deleteContentBackward / deleteContentForward beforeinput event when deleting backward/forward in a void inline node.

Issue
Fixes: #3456

Example

Before.-.Delete.backward.in.inline.void.on.Chrome.mp4

Before.-.Delete.forward.in.inline.void.on.Chrome.mp4

After.-.Delete.backward.in.inline.void.on.Chrome.mp4

After.-.Delete.forward.in.inline.void.on.Chrome.mp4

Checks

• The new code matches the existing patterns and styles.
• The tests pass with yarn test.
• The linter passes with yarn lint. (Fix errors with yarn fix.)
• The relevant examples still work. (Run examples with yarn start.)
• You've added a changeset if changing functionality. (Add one with yarn changeset add.)

[changeset-bot]

🦋 Changeset detected

Latest commit: 18044d5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
slate-react	Patch

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