Failed to download yocto repo

[YU CHENGDE]

Brief Description
-----------------
In the process of distro layered build, after running "repo sync", the error log show it can't connect to git.yoctoproject.org

Severity
--------
Miner

Steps to Reproduce
------------------
follow the layered build document
https://docs.starlingx.io/developer_resources/layered_build_guide.html
repo sync -j`nproc`

Expected Behavior
------------------
Synchronize repo successful

Actual Behavior
----------------
Synchronize repo failed

Reproducibility
---------------
Always

Timestamp/Logs
--------------
linux-yocto.git:
fatal: unable to connect to git.yoctoproject.org:
git.yoctoproject.org[0: 198.145.29.90]: errno=Connection timed out
error: Cannot fetch linux-yocto.git from git://git.yoctoproject.org/linux-yocto.git

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/manifest/+/846587

[OpenStack Infra (hudson-openstack)]

Change abandoned by "YU CHENGDE <email address hidden>" on branch: master
Review: https://review.opendev.org/c/starlingx/manifest/+/846587
Reason: No need to change