Fix spelling

src/scanner.c

@@ -3523,7 +3523,7 @@
                 if (leading_blanks && (int)parser->mark.column < indent
                         && IS_TAB(parser->buffer)) {
                     yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
-                            start_mark, "found a tab character that violate indentation");
+                            start_mark, "found a tab character that violates indentation");
                     goto error;
                 }