ghproxy: update GHPROXY_ADDRESS to ghgo.xyz

[amazingfate]

Description

ghp.ci is blocked now: https://ghproxy.link/
We have to move to new address ghgo.xyz

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Please also note any relevant details for your test configuration.

• ./compile.sh kernel-config BOARD=rock-5b BRANCH=vendor BUILD_MINIMAL=no DEB_COMPRESS=xz KERNEL_CONFIGURE=no RELEASE=noble GITHUB_MIRROR=ghproxy KERNEL_GIT=shallow

Checklist:

Please delete options that are not relevant.

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules