Fix rustc test suite

Author: bjorn3

scripts/test_rustc_tests.sh

@@ -130,6 +130,7 @@ rm tests/ui/abi/large-byval-align.rs # exceeds implementation limit of Cranelift
 rm -r tests/run-make/remap-path-prefix-dwarf # requires llvm-dwarfdump
 rm -r tests/run-make/compiler-builtins # Expects lib/rustlib/src/rust to contains the standard library source
 rm -r tests/run-make/missing-unstable-trait-bound # This disables support for unstable features, but running cg_clif needs some unstable features
+rm -r tests/run-make/const-trait-stable-toolchain # same
 
 # genuine bugs
 # ============