fix: use PropsWithChildren

@types/react v17 added the children prop automatically. This changed
with v18. Now, PropsWithChildren needs to be manually added.

Author: andipaetzold

index.d.ts

@@ -89,7 +89,7 @@ declare module 'react-helmet-async' {
     };
   }
 
-  export class HelmetProvider extends React.Component<ProviderProps> {
+  export class HelmetProvider extends React.Component<React.PropsWithChildren<ProviderProps>> {
     static canUseDOM: boolean;
   }
 }