Add actiondoc for `pop` action

actions.jsonc

@@ -147,5 +147,12 @@
     "args": "LSKEYS <limit>",
     "desc": "Returns a flat string array of keys present in the database. If no <limit> is given, then a maximum of 10 keys are returned. If a limit is specified, then a maximum of <limit> keys are returned",
     "return": "Returns a maximum of 10 keys if no limit is specified or returns a maximum number of keys for the given limit. The order of keys returned is meaningless."
+  },
+  {
+    "name": "POP",
+    "complexity": "O(n)",
+    "args": "POP <key1> <key2> ...",
+    "desc": "Deletes and returns the values of the provided keys. If the database is poisoned, this will return a server error. An exceptional scenario can arise when the database fails in-between removing all the keys. In that case, you get the server error response code instead of the keys. If the server recovers inbetween, then the appropriate values (if any) will be returned. In all other cases a NIL error is returned (code 1)",
+    "return": "Returns an array with either the values or response codes as the elements"
   }
 ]