feat: traffic-split plugin support https

[TenYearsIn]

Description

Fixes #8996

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)

[monkeyDluffy6017]

Hi @TenYearsIn, test cases are needed and please make the ci pass

[TenYearsIn]

The Test case (traffic-split2.t) 11 seems that there was some problem, I used the original code to test it, but it still fails

[soulbird]

Without your modification, I can also run the test case through.
In general, adding new functionality should not change existing test cases.

[shreemaan-abhishek]

@TenYearsIn, I can add test cases here if you add me as a collaborator in your apisix forked repository.

https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-personal-account-on-github/managing-access-to-your-personal-repositories/inviting-collaborators-to-a-personal-repository

[TenYearsIn]

@TenYearsIn, I can add test cases here if you add me as a collaborator in your apisix forked repository.

https://docs.github.com/en/account-and-profile/setting-up-and-managing-your-personal-account-on-github/managing-access-to-your-personal-repositories/inviting-collaborators-to-a-personal-repository

Let me try again. if not. do so @shreemaan-abhishek

[shreemaan-abhishek]

@TenYearsIn, please provide access to me to your forked repository.

[TenYearsIn]

@shreemaan-abhishek done

[monkeyDluffy6017]

The test case can pass without your pr

[shreemaan-abhishek]

looks like using upstream_id supports https but using real upstream is not supported, I have pushed my changes now, please review.