Secrets defined by a store are referenced with `@{<store-id>:<secret_key>}`
the Telegraf configuration. Only certain Telegraf plugins and options of
support secret stores. To see which plugins and options support
secrets, see their respective documentation (e.g.
`plugins/outputs/influxdb/README.md`). If the plugin's README has the
`Secret-store support` section, it will detail which options support secret
store usage.