patch 8.2.2661: leaking memory when looping over a string

Problem:    Leaking memory when looping over a string.
Solution:   Free the memory.

src/eval.c

@@ -1815,8 +1815,10 @@ next_for_item(void *fi_void, char_u *arg)
 	tv.v_lock = VAR_FIXED;
 	tv.vval.v_string = vim_strnsave(fi->fi_string + fi->fi_byte_idx, len);
 	fi->fi_byte_idx += len;
-	return ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
+	result = ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
 					    fi->fi_varcount, flag, NULL) == OK;
+	vim_free(tv.vval.v_string);
+	return result;
     }
 
     item = fi->fi_lw.lw_item;

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2661,
 /**/
     2660,
 /**/