Fix PathMethod object types

Author: mikestopcontinues

packages/openapi-fetch/src/index.d.ts

@@ -169,17 +169,19 @@ export interface Middleware {
   onResponse?: typeof onResponse;
 }
 
+type PathMethods = Partial<Record<HttpMethod, {}>>;
+
 /** This type helper makes the 2nd function param required if params/requestBody are required; otherwise, optional */
 export type MaybeOptionalInit<
-  P extends Record<HttpMethod, {}>,
+  P extends PathMethods,
   M extends keyof P,
 > =
   HasRequiredKeys<FetchOptions<FilterKeys<P, M>>> extends never
     ? [(FetchOptions<FilterKeys<P, M>> | undefined)?]
     : [FetchOptions<FilterKeys<P, M>>];
 
 export type ClientMethod<
-  Paths extends Record<string, Record<HttpMethod, {}>>,
+  Paths extends Record<string, PathMethods>,
   M extends HttpMethod,
 > = <
   P extends PathsWithMethod<Paths, M>,