CI/CD - Fix python3.10 pipeline (#753)

**Description**
Python3.10 pipeline failed.

**Solution**
From log, 'bc' cmd is missing. Since our image tags are simple, the
solution is to remove 'bc' cmd directly.

---------
Co-authored-by: Hongtao Zhang <hongtaozhang@microsoft.com>

.azure-pipelines/cpu-unit-test.yml

@@ -26,7 +26,7 @@ steps:
       echo "##vso[task.prependpath]$HOME/.local/bin"
     displayName: Export path
   - script: |
-      if [[ "$(echo $(imageTag) '< 3.11' | bc -l)" == 1 ]]; then
+      if python3 -c "import sys; exit(0 if sys.version_info < (3, 11) else 1)"; then
         python3 -m pip install --upgrade pip setuptools==65.7
       else
         python3 -m pip install --upgrade pip