GH-45305: [CI][Python] Temporarily avoid newer boto3 version (#45311)

Until Minio gets fixed.

* GitHub Issue: #45305

Authored-by: Antoine Pitrou <[email protected]>
Signed-off-by: Antoine Pitrou <[email protected]>

Author: pitrou

ci/appveyor-cpp-setup.bat

@@ -70,7 +70,6 @@ conda create -n arrow ^
   "ninja" ^
   "nomkl" ^
   "pandas" ^
-  "fsspec" ^
   "python=%PYTHON%" ^
   || exit /B
 conda list -n arrow