Fix linkage-attr/issue-10755.rs ui test on WSL

It checked for a "not found", but on WSL with appendWindowsPath=true,
PermissionDenied is the error instead.

Author: Noratrieb

src/test/ui/linkage-attr/issue-10755.rs

@@ -1,7 +1,10 @@
 // build-fail
 // dont-check-compiler-stderr
 // compile-flags: -C linker=llllll -C linker-flavor=ld
-// error-pattern: linker `llllll` not found
+// error-pattern: `llllll`
+
+// Before, the error-pattern checked for "not found". On WSL with appendWindowsPath=true, running
+// in invalid command returns a PermissionDenied instead.
 
 fn main() {
 }