[styled-components] Remove unneeded annotation

This raises an implicitAny error in 3.7, but builds correctly on older versions.

types/styled-components/test/index.tsx

@@ -728,7 +728,7 @@ async function typedThemes() {
         ${({ ok }: { ok: boolean }) =>
             ok &&
             css`
-                color: ${({ theme: { color } }: { theme: typeof theme }) => color};
+                color: ${({ theme: { color } }) => color};
             `}
     `;