Fix wasm tests

Looks like `cargo test` is now trying to test too many files due to
rust-lang/cargo#4750 so add a clause to the wrapper to ignore the bogus ones for
now

ci/docker/wasm32-unknown-emscripten/node-wrapper.sh

@@ -7,5 +7,9 @@ shift
 dir=$(dirname $me)
 file=$(basename $me)
 
+if echo $file | grep -q wasm; then
+  exit 0 # FIXME(rust-lang/cargo#4750)
+fi
+
 cd $dir
 exec node $file "$@"