* refactor github package and use builder pattern for client
* switch to github package
* some renamings
* fix panic on uninitialized provider
* fix according to review comments
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Co-authored-by: Gulom Alimov <gulomjon.alimov@sap.com>
Co-authored-by: Jordi van Liempt <35920075+jliempt@users.noreply.github.com>