patch 8.2.3887: E1135 is used for two different errors

Problem:    E1135 is used for two different errors.
Solution:   Renumber one error.

src/errors.h

@@ -603,8 +603,6 @@ EXTERN char e_cannot_extend_null_list[]
 EXTERN char e_using_string_as_bool_str[]
 	INIT(= N_("E1135: Using a String as a Bool: \"%s\""));
 #endif
-EXTERN char e_cmd_mapping_must_end_with_cr[]
-	INIT(=N_("E1135: <Cmd> mapping must end with <CR>"));
 EXTERN char e_cmd_mapping_must_end_with_cr_before_second_cmd[]
 	INIT(= N_("E1136: <Cmd> mapping must end with <CR> before second <Cmd>"));
 EXTERN char e_cmd_maping_must_not_include_str_key[]
@@ -852,3 +850,5 @@ EXTERN char e_string_expected_for_argument_nr[]
 	INIT(= N_("E1253: String expected for argument %d"));
 EXTERN char e_cannot_use_script_variable_in_for_loop[]
 	INIT(= N_("E1254: Cannot use script variable in for loop"));
+EXTERN char e_cmd_mapping_must_end_with_cr[]
+	INIT(= N_("E1255: <Cmd> mapping must end with <CR>"));

src/testdir/test_mapping.vim

@@ -905,7 +905,7 @@ func Test_map_cmdkey()
   call assert_equal(0, x)
 
   noremap <F3> <Cmd>let x = 3
-  call assert_fails('call feedkeys("\<F3>", "xt!")', 'E1135:')
+  call assert_fails('call feedkeys("\<F3>", "xt!")', 'E1255:')
   call assert_equal(0, x)
 
   " works in various modes and sees the correct mode()

src/version.c

@@ -749,6 +749,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3887,
 /**/
     3886,
 /**/