## Summary
Hashicorp Vault prefers a `LIST` HTTP method to be used when fetching
secrets but not all environments will allow custom http methods through
WAFs. This PR adds `N8N_EXTERNAL_SECRETS_PREFER_GET` which when set to
`true` will use GET instead of LIST to fetch secrets.
## Review / Merge checklist
- [x] PR title and summary are descriptive. **Remember, the title
automatically goes into the changelog. Use `(no-changelog)` otherwise.**
([conventions](https://github.com/n8n-io/n8n/blob/master/.github/pull_request_title_conventions.md))
## Summary
Adds `N8N_EXTERNAL_SECRETS_UPDATE_INTERVAL` to allow enterprise users to
tweak the update internal for importing new secrets.
If using a config file the value is:
```
"externalSecrets": {
"updateInterval": 300
}
```
#### How to test the change:
1. Run as normal and check that the secret is updated every 5 minutes
2. Set `N8N_EXTERNAL_SECRETS_UPDATE_INTERVAL` to 10
3. Check the secret is reloaded after 10 seconds
## Review / Merge checklist
- [x] PR title and summary are descriptive. **Remember, the title
automatically goes into the changelog. Use `(no-changelog)` otherwise.**
([conventions](https://github.com/n8n-io/n8n/blob/master/.github/pull_request_title_conventions.md))
- [x] [Docs updated](https://github.com/n8n-io/n8n-docs) or follow-up
ticket created.