[docker] Update pip install

It looks like Python has adjusted the get-pip.py URL to no longer
support Python 2.7. This patch updates the Docker scripts to
use the 2.7 specific URL and drop the old 2.6 speicific url now
that no supported images use Python 2.6.

Change-Id: Ia9a22e5084f8a5973d26372372f2ead4c46dcda9
Reviewed-on: http://gerrit.cloudera.org:8080/16984
Tested-by: Kudu Jenkins
Reviewed-by: Alexey Serbin <[email protected]>

docker/bootstrap-dev-env.sh

@@ -77,7 +77,7 @@ if [[ -f "/usr/bin/yum" ]]; then
   # to install the ninja-build package.
   if [[ "$OS_MAJOR_VERSION" -gt "7" ]]; then
     yum install -y 'dnf-command(config-manager)'
-    yum config-manager --set-enabled PowerTools
+    yum config-manager --set-enabled powertools
   fi
 
   # Install libraries often used for Kudu development and build performance.

docker/bootstrap-python-env.sh

@@ -34,14 +34,13 @@ function install_python_packages() {
   # We use get-pip.py to bootstrap pip outside of system packages.
   # This prevents issues with the platform package manager knowing
   # about only some of the python packages.
-  if [[ "$PYTHON_MAJOR" == "2" && "$PYTHON_MINOR" == "6" ]]; then
-    # Beginning with pip 10, Python 2.6 is no longer supported.
-    curl https://bootstrap.pypa.io/2.6/get-pip.py | python
+  if [[ "$PYTHON_MAJOR" == "2" && "$PYTHON_MINOR" == "7" ]]; then
+    # The standard get-pip.py URL no longer supports Python 2.7,
+    # so we need to use the version specific one.
+    curl https://bootstrap.pypa.io/2.7/get-pip.py | python
   else
-    # Use a stable version of pip that works with the remaining
-    # versions of Python 2 and 3. pip 19.1 doesn't support Python 3.4,
-    # which is the version of Python 3 shipped with Ubuntu 14.04.
-    curl https://bootstrap.pypa.io/get-pip.py | python - "pip < 19.0"
+    # Use a stable version of pip that works with Python 2 and 3.
+    curl https://bootstrap.pypa.io/get-pip.py | python - "pip < 20.3.4"
   fi
   pip install --upgrade \
     cython \