fix(API): remove unused std_misc feature

Hopefully this will not trigger errors elsewhere, but we will
just find out I guess ;)

src/mako/api/lib.rs.mako

@@ -22,7 +22,6 @@
 <%block filter="rust_module_doc_comment">\
 ${lib.docs(c)}
 </%block>
-#![feature(std_misc)]
 // Unused attributes happen thanks to defined, but unused structures
 // We don't warn about this, as depending on the API, some data structures or facilities are never used.
 // Instead of pre-determining this, we just disable the lint. It's manually tuned to not have any