Docs: API: Update token_period description (hashicorp#19821)

- Clarify token_period per feedback in SPE-34

website/content/partials/tokenstorefields.mdx

@@ -13,9 +13,7 @@
   token may be used (within its lifetime); 0 means unlimited.
   If you require the token to have the ability to create child tokens,
   you will need to set this value to 0.
-- `token_period` `(integer: 0 or string: "")` - The
-  [period](/vault/docs/concepts/tokens#token-time-to-live-periodic-tokens-and-explicit-max-ttls),
-  if any, to set on the token.
+- `token_period` `(integer: 0 or string: "")` - The maximum allowed [period](/vault/docs/concepts/tokens#token-time-to-live-periodic-tokens-and-explicit-max-ttls) value when a periodic token is requested from this role.
 - `token_type` `(string: "")` - The type of token that should be generated. Can
   be `service`, `batch`, or `default` to use the mount's tuned default (which
   unless changed will be `service` tokens). For token store roles, there are two