Remove extra comma in Image Pull API examples

Signed-off-by: Anton Tiurin <noxiouz@yandex.ru>

docs/reference/api/docker_remote_api_v1.22.md

@@ -1727,7 +1727,7 @@ Query Parameters:
     {
             "username": "jdoe",
             "password": "secret",
-            "email": "jdoe@acme.com",
+            "email": "jdoe@acme.com"
     }
         ```
 

docs/reference/api/docker_remote_api_v1.23.md

@@ -1758,7 +1758,7 @@ Query Parameters:
     {
             "username": "jdoe",
             "password": "secret",
-            "email": "jdoe@acme.com",
+            "email": "jdoe@acme.com"
     }
         ```
 

docs/reference/api/docker_remote_api_v1.24.md

@@ -1759,7 +1759,7 @@ a base64-encoded AuthConfig object.
     {
             "username": "jdoe",
             "password": "secret",
-            "email": "jdoe@acme.com",
+            "email": "jdoe@acme.com"
     }
         ```
 

docs/reference/api/docker_remote_api_v1.25.md

@@ -1760,7 +1760,7 @@ a base64-encoded AuthConfig object.
     {
             "username": "jdoe",
             "password": "secret",
-            "email": "jdoe@acme.com",
+            "email": "jdoe@acme.com"
     }
         ```