Add option to make the destination repo private

Useful if you're copying a public repository but don't want to make the destination one public

Think I did this right, difficult to test :D

app.py

@@ -9,7 +9,7 @@ ENDPOINT = "https://huggingface.co"
 REPO_TYPES = ["model", "dataset", "space"]
 
 
-def duplicate(source_repo, dst_repo, token, repo_type):
+def duplicate(source_repo, dst_repo, token, repo_type, private):
     try:
         if not repo_type in REPO_TYPES:
             raise ValueError("need to select valid repo type")
@@ -19,7 +19,7 @@ def duplicate(source_repo, dst_repo, token, repo_type):
         r = requests.post(
             f"{ENDPOINT}/api/{repo_type}s/{source_repo}/duplicate",
             headers=build_hf_headers(token=token),
-            json={"repository": dst_repo},
+            json={"repository": dst_repo, "private": private},
         )
         hf_raise_for_status(r)
 
@@ -48,6 +48,7 @@ interface = gr.Interface(
         gr.Textbox(placeholder="Destination repository (e.g. osanseviero/dst)"),
         gr.Textbox(placeholder="Write access token", type="password"),
         gr.Dropdown(choices=REPO_TYPES, value="model"),
+        gr.Checkbox(label="Make new repo private?"),
     ],
     outputs=[
         gr.Markdown(label="output"),