Input static field not updating

On Graylog 5.2.6 when you update or change the static field of an input, the change is not applied to the logs being processed. The UI shows the change on the input page, but the logs continue to use the old value. I ended up having to delete the input and re-create it to use different values for the static field. I've tested this on a tcp raw kafka input and a tcp/syslog input.

Steps to reproduce:

- Create an input
- Add static field and value
- Collect logs and note the field
- Change the static field value
- Note the logs are still using the old value