docs(preact-query/devtools): add missing 'relative' to 'buttonPosition' (TanStack#10611)

Author: sukvvon

docs/framework/preact/devtools.md

@@ -70,7 +70,7 @@ function App() {
 
 - `initialIsOpen: boolean`
   - Set this `true` if you want the dev tools to default to being open
-- `buttonPosition?: "top-left" | "top-right" | "bottom-left" | "bottom-right"`
+- `buttonPosition?: "top-left" | "top-right" | "bottom-left" | "bottom-right" | "relative"`
   - Defaults to `bottom-right`
   - The position of the Preact Query logo to open and close the devtools panel
 - `position?: "top" | "bottom" | "left" | "right"`