Failures due to new --limit feature

[jawnsy]

The default value of None for --limit for the agent and worker seem to be causing crash loops upon upgrade.

$ helm upgrade --install --reset-values --set=worker.apiConfig=server --set=worker.serverApiConfi.apiUrl=http://prefect-server.jawnsy-test.svc.cluster.local:4200/api --set=worker.config.workPool=test prefect-worker ./ch
arts/prefect-worker/
Release "prefect-worker" has been upgraded. Happy Helming!
NAME: prefect-worker
LAST DEPLOYED: Mon Jul  3 08:41:54 2023
NAMESPACE: jawnsy-test
STATUS: deployed
REVISION: 2
TEST SUITE: None
NOTES:
1. Check Prefect worker connections in the prefect UI at "http://127.0.0.1:4200/api"
[gke_prefect-dev-internal-tools_us-east1_internal-tools-dev-main|jawnsy-test] 08:41 jawnsy@consilience 

$ k get pod
NAME                              READY   STATUS    RESTARTS     AGE
prefect-server-6fd4f464bf-jsxnk   1/1     Running   0            75s
prefect-worker-599d68d85d-kv94w   1/1     Running   1 (1s ago)   3s

$ k logs prefect-worker-599d68d85d-kv94w
Usage: prefect worker start [OPTIONS]
Try 'prefect worker start --help' for help.
╭─ Error ──────────────────────────────────────────────────────────────────────╮
│ Invalid value for '-l' / '--limit': 'None' is not a valid integer.           │
╰──────────────────────────────────────────────────────────────────────────────╯