use void for options hook instead of undefined

currently we are required to return in the options hook. this change would allow the options hook to have no return value.

src/rollup/types.d.ts

@@ -381,7 +381,7 @@ export interface PluginHooks extends OutputPluginHooks {
 	options: (
 		this: MinimalPluginContext,
 		options: InputOptions
-	) => Promise<InputOptions | null | undefined> | InputOptions | null | undefined;
+	) => Promise<InputOptions | null | void> | InputOptions | null | void;
 	resolveDynamicImport: ResolveDynamicImportHook;
 	resolveId: ResolveIdHook;
 	shouldTransformCachedModule: ShouldTransformCachedModuleHook;