Ensure we handle resourcepaths with a querystring correctly

Without this change, we generated a broken querystring with two questionmarks.

Author: Tom Hendrikx

mollie/api/client.py

@@ -181,7 +181,11 @@ def _format_request_data(
 
         querystring = generate_querystring(params)
         if querystring:
-            url += "?" + querystring
+            if "?" in url:
+                # There is already a querystring in the URL
+                url += "&" + querystring
+            else:
+                url += "?" + querystring
             params = None
 
         return url, payload, params
@@ -204,7 +208,6 @@ def _perform_http_call_apikey(
 
         url, payload, params = self._format_request_data(path, data, params)
         try:
-
             headers = {
                 "Accept": "application/json",
                 "Authorization": f"Bearer {self.api_key}",
@@ -239,7 +242,6 @@ def _perform_http_call_oauth(
     ) -> requests.Response:
         url, payload, params = self._format_request_data(path, data, params)
         try:
-
             headers = {
                 "Accept": "application/json",
                 "Content-Type": "application/json",

tests/test_profile_chargebacks.py

@@ -21,3 +21,11 @@ def test_list_profile_chargebacks(oauth_client, response):
     assert chargebacks.has_next()
     more_chargebacks = chargebacks.get_next()
     assert_list_object(more_chargebacks, Chargeback)
+
+
+def test_list_profile_chargebacks_with_params(oauth_client, response):
+    response.get(f"https://api.mollie.com/v2/profiles/{PROFILE_ID}", "profile_single")
+    response.get(f"https://api.mollie.com/v2/chargebacks?profileId={PROFILE_ID}&limit=42", "profile_chargebacks_list")
+
+    profile = oauth_client.profiles.get(PROFILE_ID)
+    profile.chargebacks.list(limit=42)