Improve non-ice-error-on-worker-io-fail.rs test

- Remove unrelated code
- Use a local dir path

Author: WaffleLapkin

tests/ui/io-checks/non-ice-error-on-worker-io-fail.rs

@@ -9,7 +9,7 @@
 // up clobbering `/dev/null`. Instead we'll use a non-existent path, which
 // also used to ICE, but even root can't magically write there.
 
-// compile-flags: -o /does-not-exist/output
+// compile-flags: -o ./does-not-exist/output
 
 // The error-pattern check occurs *before* normalization, and the error patterns
 // are wildly different between build environments. So this is a cop-out (and we
@@ -19,22 +19,14 @@
 // error-pattern: error
 
 // On Mac OS X, we get an error like the below
-// normalize-stderr-test "failed to write bytecode to /does-not-exist/output.non_ice_error_on_worker_io_fail.*" -> "io error modifying /does-not-exist/"
+// normalize-stderr-test "failed to write bytecode to ./does-not-exist/output.non_ice_error_on_worker_io_fail.*" -> "io error modifying ./does-not-exist/"
 
 // On Linux, we get an error like the below
-// normalize-stderr-test "couldn't create a temp dir.*" -> "io error modifying /does-not-exist/"
+// normalize-stderr-test "couldn't create a temp dir.*" -> "io error modifying ./does-not-exist/"
 
 // ignore-windows - this is a unix-specific test
 // ignore-emscripten - the file-system issues do not replicate here
 // ignore-wasm - the file-system issues do not replicate here
 // ignore-arm - the file-system issues do not replicate here, at least on armhf-gnu
 
-#![crate_type="lib"]
-
-#![cfg_attr(not(feature = "std"), no_std)]
-pub mod task {
-    pub mod __internal {
-        use crate::task::Waker;
-    }
-    pub use core::task::Waker;
-}
+#![crate_type = "lib"]

tests/ui/io-checks/non-ice-error-on-worker-io-fail.stderr

@@ -1,6 +1,6 @@
 warning: ignoring --out-dir flag due to -o flag
 
-error: io error modifying /does-not-exist/
+error: io error modifying ./does-not-exist/
 
 error: aborting due to previous error; 1 warning emitted