optimize: avoid generating drop glue for StepResult

fix-vm/src/bytecode_reader.rs

@@ -77,6 +77,7 @@ impl<'a> BytecodeReader<'a> {
     #[inline(always)]
     pub(crate) fn read_string_id(&mut self) -> StringId {
         let raw = self.read_u32();
+        #[allow(clippy::unwrap_used)]
         StringId(string_interner::symbol::SymbolU32::try_from_usize(raw as usize).unwrap())
     }