[CI] Conda configuration to retry after gateway error

Solving environment: ...working... failed
CondaHTTPError: HTTP 504 GATEWAY TIME-OUT for url <https://conda.anaconda.org/conda-forge/linux-64/repodata.json>
Elapsed: 00:10.069098
CF-RAY: 4430bab78cbf54f8-ORD
A remote server error occurred when trying to retrieve this URL.
A 500-type error (e.g. 500, 501, 502, 503, etc.) indicates the server failed to
fulfill a valid request.  The problem may be spurious, and will resolve itself if you
try your request again.  If the problem persists, consider notifying the maintainer
of the remote server.