Reimplement GetUserOrgsList and also move some functions and test to
org_list file.
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Co-authored-by: Zettat123 <zettat123@gmail.com>
(cherry picked from commit b4abb6deff14b741c7666d7579e0eea68443306c)
Conflicts:
models/organization/org_test.go
services/oauth2_provider/access_token.go
trivial conflicts due to codeblocks moving to different files
