API add unsubscribe example (#5965)

docs/en/developers/06_GoogleReader_API.md

@@ -67,6 +67,10 @@ curl -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60
 # Get articles, piped to jq for easier JSON reading
 curl -s -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60bdb5f8" \
   'https://freshrss.example.net/api/greader.php/reader/api/0/stream/contents/reading-list' | jq .
+
+# Unsubscribe from a feed
+curl -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60bdb5f8" \
+  -d 'ac=unsubscribe&s=feed/52' 'https://freshrss.example.net/api/greader.php/reader/api/0/subscription/edit'
 ```
 
 * [Source code of our API implementation](https://github.com/FreshRSS/FreshRSS/blob/edge/p/api/greader.php)

docs/fr/users/06_Mobile_access.md

@@ -100,4 +100,8 @@ curl -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60
 # Récupère les articles, envoyés à jq pour une lecture JSON plus facile
 curl -s -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60bdb5f8" \
   'https://freshrss.example.net/api/greader.php/reader/api/0/stream/contents/reading-list' | jq .
+
+# Se désabonner d’un flux
+curl -H "Authorization:GoogleLogin auth=alice/8e6845e089457af25303abc6f53356eb60bdb5f8" \
+  -d 'ac=unsubscribe&s=feed/52' 'https://freshrss.example.net/api/greader.php/reader/api/0/subscription/edit'
 ```