[ci] Remove protobuf pin to < 4 (repeat) (ray-project#29584)

ray-project#29224 removed the protobuf upper bound but ray-project#29375 was oroginally created on an older requirements file and accidentally reverted the update for unix builds.

Signed-off-by: Kai Fricke <kai@anyscale.com>
Signed-off-by: Weichen Xu <weichen.xu@databricks.com>

Author: krfricke

python/requirements.txt

@@ -12,8 +12,7 @@ click<=8.0.4,>=7.0
 filelock
 jsonschema
 msgpack<2.0.0,>=1.0.0
-protobuf<4.0.0,>=3.15.35; platform_system != "Windows"
-protobuf>= 3.15.3, != 3.19.55; platform_system == "Windows"
+protobuf>= 3.15.3, != 3.19.55
 pyyaml
 aiosignal
 frozenlist