set a plugin repository, too

switched the Maven repository

[maven-release-plugin] copy for tag github-api-1.4

[maven-release-plugin] copy for tag github-api-1.3

[maven-release-plugin] copy for tag github-api-1.2

[maven-release-plugin] copy for tag github-api-1.1

[maven-release-plugin] copy for tag github-api-1.0