erp5: Add oic library for OpenIdConnect

* Note from @jerome: We have a useless dependency to
 https://pypi.org/project/alabaster/, a sphynx theme,
 but with oic v0.15.1 it's listed as a dependency
 ( https://github.com/OpenIDC/pyoidc/blob/v0.15.1/setup.py#L89 )
 so we don't have a choice. It was fixed later
 ( https://github.com/OpenIDC/pyoidc/issues/598 )
 but after python2 support was dropped.

stack/erp5/buildout.cfg

@@ -557,6 +557,9 @@ eggs = ${neoppod:eggs}
   zope.globalrequest
   waitress
 
+# OpenId Connect
+  oic
+
 # parameterizing the version of the generated python interpreter name by the
 # python section version causes dependency between this egg section and the
 # installation of python, which we don't want on an instance
@@ -756,3 +759,11 @@ beautifulsoup4 = 4.8.2
 WebOb = 1.8.5
 soupsieve = 1.9.5
 eggtestinfo = 0.3
+
+oic = 0.15.1
+Beaker = 1.11.0
+Mako = 1.1.4
+pyjwkest = 1.4.2
+alabaster = 0.7.12
+future = 0.18.2
+pycryptodomex = 3.10.1