Improve Sentry Error Filtering

[JacobMGEvans]

fix: We want to prevent any user created code from sending Events to Sentry,
which can be captured by uncaughtExceptionMonitor listener.
Miniflare code can run user code on the same process as Wrangler, so we want to return null
if "@miniflare" is present in the Event frames.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1004c70

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

This PR includes changesets to release 1 package

Name	Type
wrangler	Patch

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/runs/2150908543/npm-package-wrangler-772

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/prs/772/npm-package-wrangler-772

Or you can use npx with this latest build directly:

npx https://prerelease-registry.developers.workers.dev/runs/2150908543/npm-package-wrangler-772 dev path/to/script.js

[petebacondarwin]

Probably should have a changeset, I think