Add python3-pip to list of installed packages

OSH requires pip3 to install the openstackclient, and a recent
change in infra made the images no longer contain
pip by default. This change adds python3-pip in order to address
this.

Change-Id: I32febc7194ced6ab88794c6ac9fa2aa373909827

tools/deployment/common/install-packages.sh

@@ -23,4 +23,5 @@ sudo apt-get install --no-install-recommends -y \
         nmap \
         curl \
         uuid-runtime \
-        bc
+        bc \
+        python3-pip