Bump sentry/sentry from 4.18.0 to 4.18.1 in /_backend (#3899)

Bumps [sentry/sentry](https://github.com/getsentry/sentry-php) from 4.18.0 to 4.18.1.
- [Release notes](https://github.com/getsentry/sentry-php/releases)
- [Changelog](https://github.com/getsentry/sentry-php/blob/master/CHANGELOG.md)
- [Commits](getsentry/sentry-php@4.18.0...4.18.1)

---
updated-dependencies:
- dependency-name: sentry/sentry
  dependency-version: 4.18.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]