Worker: ignore sentry errors `Credential environment mismatch`

We're seeing another user error on sentry:

[fetch:credential] Credential environment mismatch.
This project is using 'geda' but credential 'Pius Git Token' does not have a matching environment. To fix:
  1. Go to https://app.openfn.org/projects/a36ac16e-3b46-4bfa-a9b8-4ad5975bafb0/settings#credentials
  2. Find 'Pius Git Token'
  3. Click 'Edit' and add an environment named 'geda'
Or change your project environment to match an existing credential environment.

This error is thrown in a projeect when you select a credential that does not have a value for a given environment. For example, you have a sandbox in dev but your credential only has a main

This is a perfectly OK and expected user error. It should be supressed from sentry. See #1440 for a reference fix

example error

Start with the worker's Sentry error-reporting path and use issue #1440 as the reference fix. Reproduce or inspect the Credential environment mismatch error, then verify that this expected user error is suppressed from Sentry while other errors remain reported.