Added back content type header for login request

Author: sneakernuts

crates/bitwarden-uniffi/swift/iOS/App/ContentView.swift

@@ -160,7 +160,10 @@ struct ContentView: View {
         let (loginDataJson, _) = try await http.data(
             for: request(
                 method: "POST", url: IDENTITY_URL + "connect/token",
-                fn: {
+                fn: { r in 
+                    r.setValue(
+                        "application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
+                    
                     var comp = URLComponents()
                     comp.queryItems = [
                         URLQueryItem(name: "scope", value: "api offline_access"),