replaced oltu with scribejava for Java - okhttp client

[valmoz]

#10661

This PR replaces the deprecated Apache Oltu library with ScribeJava for the Java OkHttp client.
It also tries to improve the OAuth code as follows:

• uniforming the OAuth authentication to the other auth methods, managing the Authentication as a parameter instead of using an OkHttp interceptor;
• introducing the AuthorizationCode, Password, and ClientCredentials Grants;
• managing authorization URL, refresh URL, and scope parameters for the oauth2 config.

this replaces #10732

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@wing328 @bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608 @nmuesch

[DFromTheHood]

Can this PR be completed soon?

[RockyMM]

Maybe @wing328 or @jmini could take a look?

[valmoz]

I admit that I let this PR die, I didn't have enough time to complete it.
If it is still of interest, I can try to recover it, adapting it to the new versions... I don't know when I'll be able to work on it though

[RockyMM]

Ah, too bad, as it is a very welcome improvent. I could maybe dedicate some time in the future for this, but it is very unlikely, I guess we are all in the same boat :D

[hroig]

Are there any plans to resurrect this branch?

[valmoz]

Hi @hroig
unfortunately I didn't have time to dedicate to it. If I'll be able to find some time during the incoming summer I'll try to complete it, but I can't assure anything.
If somebody wants to try and complete it, it could be a great help.

[chilphil]

how is it going?