feat: openid-connect as auth plugin

[coiouhkc]

Description

This PR adds auth plugin functionality to openid-connect using preferred_username token claim and respective field in consumers to identify and attach the consumer for further needs, e.g. consumer-restriction.

Fixes # (issue)

• bug: How to correctly create a consumer with openid-connect? #11015
• Hope to support oidc+consumer-restriction whitelist+consumer to implement different system calls #9093 ?

Checklist

• I have explained the need for this PR and the problem it solves
• I have explained the changes or the new features added to this PR
• I have added tests corresponding to this change
• I have updated the documentation to reflect this change
• I have verified that this change is backward compatible (If not, please discuss on the APISIX mailing list first)

[coiouhkc]

Dear maintainers (@kayx23 ?), please advise if the suggested feature is acceptable so that I could continue working on the PR (fix the code, write tests, update docu, etc.)

[kayx23]

cc: @shreemaan-abhishek @bzp2010 @moonming

[coiouhkc]

@shreemaan-abhishek @bzp2010 @moonming - friendly reminder, please check the suggestion so that I know whether the general direction is OK.