Enabled conformance tests to run under ASAN. This apears to work now. (#292)

kokoro/ubuntu/build.sh

@@ -24,7 +24,7 @@ bazel test --test_output=errors :all
 if [[ $(uname) = "Linux" ]]; then
   # Verify the ASAN build.  Have to exclude test_conformance_upb as protobuf
   # currently leaks memory in the conformance test runner.
-  bazel test --copt=-fsanitize=address --linkopt=-fsanitize=address --test_output=errors -- :all -:test_conformance_upb
+  bazel test --copt=-fsanitize=address --linkopt=-fsanitize=address --test_output=errors :all
 
   # Verify the UBSan build. Have to exclude Lua as the version we are using
   # fails some UBSan tests.