Preparing for building Sisyphus on Github Actions

Prepare "gradle.properties" needed by sisyphus building.

Inputs to 'gradle.properties' mapping

input	gradle.properties	descriptor
developer	sisyphus.developer	Set developer name for developing environment.
snapshot-repositories	sisyphus.snapshot.repositories	Repositories for snapshot publishing, default value is snapshot.
release-repositories	sisyphus.release.repositories	Repositories for release publishing, default value is release.
docker-repositories	sisyphus.docker.repositories	Repositories for docker publishing.
config-repositories	sisyphus.config.repositories	Repositories for resolving configuration artifact, default value is local,central,jcenter,portal.
dependency-repositories	sisyphus.dependency.repositories	Repositories for resolving dependencies, default value is local,central,jcenter,portal.
config-artifacts	sisyphus.config.artifacts	Configuration artifacts.
gradle-portal-key	gradle.publish.key	Publish key for gradle portal.
gradle-portal-secret	gradle.publish.secret	Publish secret for gradle portal.
gpg-key-name	signing.gnupg.keyName	Gunpg key name of signing.

Dynamic input mapping

input	gradle.properties	descriptor
name-url	sisyphus.repositories.name.url	Url of repository.
name-username	sisyphus.repositories.name.username	Optional, user name of repository.
name-password	sisyphus.repositories.name.password	Optional, password of repository.

 Dynamic input will cause some warning of Github Actions.