Do not set inside_macro flag when converting try!() to '?'

This will keep rustfmt idempotent when using 'use_try_shorthand' config option.

src/macros.rs

@@ -118,6 +118,7 @@ pub fn rewrite_macro(
     context.inside_macro = true;
     if context.config.use_try_shorthand() {
         if let Some(expr) = convert_try_mac(mac, context) {
+            context.inside_macro = false;
             return expr.rewrite(context, shape);
         }
     }