patch 8.2.1918: Vim9: E1100 mentions :let

Problem:    Vim9: E1100 mentions :let.
Solution:   Mention "var". (closes #7207)
diff --git a/src/errors.h b/src/errors.h
index 4d8456f..1843f3d 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -27,8 +27,8 @@
 	INIT(= N_("E856: \"assert_fails()\" second argument must be a string or a list with one or two strings"));
 EXTERN char e_cannot_index_special_variable[]
 	INIT(= N_("E909: Cannot index a special variable"));
-EXTERN char e_missing_let_str[]
-	INIT(= N_("E1100: Missing :let: %s"));
+EXTERN char e_missing_var_str[]
+	INIT(= N_("E1100: Missing :var: %s"));
 EXTERN char e_variable_not_found_str[]
 	INIT(= N_("E1001: Variable not found: %s"));
 EXTERN char e_syntax_error_at_str[]
diff --git a/src/version.c b/src/version.c
index 32c42a0..a7508ca 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1918,
+/**/
     1917,
 /**/
     1916,
diff --git a/src/vim9script.c b/src/vim9script.c
index cb13f3c..3780356 100644
--- a/src/vim9script.c
+++ b/src/vim9script.c
@@ -70,7 +70,7 @@
 	    case CMD_insert:
 	    case CMD_t:
 	    case CMD_xit:
-		semsg(_(e_missing_let_str), eap->cmd);
+		semsg(_(e_missing_var_str), eap->cmd);
 		return FAIL;
 	    default: break;
 	}