chore: bump express to v4.21.0

[wrn14897]

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 18569a5bf657063c30c5c523c507f79848185f7f

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

This PR includes changesets to release 2 packages

Name	Type
@hyperdx/api	Patch
@hyperdx/app	Patch

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