Fix deprecated option in rustfmt.toml

rustfmt.toml

@@ -8,13 +8,13 @@ fn_single_line = false
 force_explicit_abi = true
 format_strings = false
 hard_tabs = false
-hide_parse_errors = false
 imports_granularity = "Crate"
 imports_indent = "Block"
 imports_layout = "Mixed"
 indent_style = "Block"
 max_width = 100
 newline_style = "Unix"
+show_parse_errors = true
 skip_children = false
 tab_spaces = 4
 trailing_comma = "Vertical"