Motivation:
We need to add `--add-exports java.base/sun.security.x509=ALL-UNNAMED` when running the tests for codec-http2 as some of the tests use SelfSignedCertificate.
Modifications:
- Add `--add-exports java.base/sun.security.x509=ALL-UNNAMED` when running the tests for codec-http2
- Ensure we export correct when running with JDK12, 13, 14 and 15 as well
Result:
No more tests failure due not be able to access classes