IWF-1: auto publish to Maven on release

[longquanzheng]

Something similar to python sdk: indeedeng/iwf-python-sdk#35

However, not sure how we can workaround the signing requirements (must be a way, need some research)

[longquanzheng]

looks like we can put the private key(signing key) like this: https://medium.com/@jtbsorensen/publish-your-artifact-to-the-maven-central-repository-using-github-actions-15d3b5d9ce88