patch 8.2.4125: completion tests fail

Problem:    Completion tests fail.
Solution:   Disable error messages while dereferencing the function name.

src/eval.c

@@ -709,7 +709,9 @@ call_vim_function(
 
     // The name might be "import.Func" or "Funcref".
     arg = func;
+    ++emsg_off;
     name = deref_function_name(&arg, &tofree, &EVALARG_EVALUATE, FALSE);
+    --emsg_off;
     if (name == NULL)
 	name = func;
 

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4125,
 /**/
     4124,
 /**/