Stabilize viewTransiton and flushSync options

[brophdawg11]

For replaying in v7:

for F in $(find . -type f -not -path "./node_modules/*" -not -path "./.git/*" -not -path "./examples/*" -not -path "./.changeset/*" -not -name "CHANGELOG.md" -not -name "*.png" -not -name "*.jpeg" -not -name "*.ico"); do sed -i '' 's/unstable_viewTransition/viewTransition/g' $F; sed -i '' 's/unstable_useViewTransition/useViewTransition/g' $F; sed -i '' 's/unstable_flushSync/flushSync/g' $F; done 

[changeset-bot]

🦋 Changeset detected

Latest commit: a3497b9

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

This PR includes changesets to release 5 packages

Name	Type
react-router-dom	Minor
react-router	Minor
@remix-run/router	Minor
react-router-dom-v5-compat	Minor
react-router-native	Minor

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[github-actions]

🤖 Hello there,

We just published version 6.27.0-pre.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!

[github-actions]

🤖 Hello there,

We just published version 6.27.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!

[github-actions]

🤖 Hello there,

We just published version 6.28.2-pre.0 which includes this pull request. If you'd like to take it for a test run please try it out and let us know what you think!

Thanks!