Add opt-level=0 to test

Author: tlively

src/test/ui/issues/issue-66308.rs

@@ -1,5 +1,5 @@
 // build-pass
-// compile-flags: --crate-type lib
+// compile-flags: --crate-type lib -C opt-level=0
 
 // Regression test for LLVM crash affecting Emscripten targets