Workbench: Pin the Python packaing package.

Otherwise pip tries to uninstall it and fails because it was installed
by APT.

workbench/Dockerfile

@@ -164,8 +164,9 @@ ENV PIPX_HOME /opt/pipx
 ENV PIPX_BIN_DIR /opt/pipx/bin
 # hadolint ignore=DL3013
 RUN export PIP_CONSTRAINT=/tmp/constraint.txt && \
-    echo 'resolvelib==0.5.4' > "$PIP_CONSTRAINT" && \
     echo 'Cython < 3.0' >> "$PIP_CONSTRAINT" && \
+    echo 'packaging==24.0' >> "$PIP_CONSTRAINT" && \
+    echo 'resolvelib==0.5.4' >> "$PIP_CONSTRAINT" && \
     python3 -m pip install --no-cache-dir --break-system-packages \
         https://github.com/aws/aws-cli/archive/refs/heads/v2.zip \
         Glances \