docs: fix output.httpClient title (#1501)

docs/src/pages/reference/configuration/output.md

@@ -39,7 +39,7 @@ module.exports = {
 
 if you want you can provide a function to extend or create you custom client generator and this function receive a [[GeneratorClients](/~https://github.com/anymaniax/orval/blob/master/packages/core/src/types.ts#L156)](/~https://github.com/anymaniax/orval/blob/master/packages/core/src/types.ts#L156) in argument and should return a [ClientGeneratorsBuilder](/~https://github.com/anymaniax/orval/blob/master/packages/core/src/types.ts#L652).
 
-### client
+### httpClient
 
 Type: `String`.