endpoints: add Battlenet endpoints

[akay]

OAuth APIs: https://develop.battle.net/documentation/battle-net/oauth-apis

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[akay]

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This PR (HEAD: e959643) has been imported to Gerrit for code review.

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Patch Set 1:

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Message from Brad Fitzpatrick:

Patch Set 1: Run-TryBot+1 Code-Review+2 Trust+1

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Patch Set 1:

(1 comment)

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Patch Set 1: TryBot-Result+1

(1 comment)

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Message from Heschi Kreinick:

Patch Set 1: Trust+1

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This PR is being closed because golang.org/cl/310249 has been merged.

[andig]

I'm wondering why new endpoints are accepted here. According to policy:

Policy for new packages

We no longer accept new provider-specific packages in this repo if all they do is add a single endpoint variable. If you just want to add a single endpoint, add it to the pkg.go.dev/golang.org/x/oauth2/endpoints package.

While this is not a new package, it is a new endpoint?