Enable extra warnings required by rust-lang/rust

crates/ide-ssr/src/lib.rs

@@ -3,6 +3,8 @@
 //! Allows searching the AST for code that matches one or more patterns and then replacing that code
 //! based on a template.
 
+#![warn(rust_2018_idioms, unused_lifetimes, semicolon_in_expressions_from_macros)]
+
 // Feature: Structural Search and Replace
 //
 // Search and replace with named wildcards that will match any expression, type, path, pattern or item.