Use python3 for CSITs

- use python3 and pip3 in scripts
- update robot-framework-http library, so it can use python3
- update selenium2library, so it can use python3

Issue-ID: POLICY-3092
Signed-off-by: arkadiusz.adamski <aadamski@est.tech>
Change-Id: I5a6a4fe43e54366859049e1d43bbce599dacd14e
diff --git a/csit/drools-pdp/plans/setup.sh b/csit/drools-pdp/plans/setup.sh
index 003f21b..3f3624f 100755
--- a/csit/drools-pdp/plans/setup.sh
+++ b/csit/drools-pdp/plans/setup.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 # ============LICENSE_START=======================================================
 # Copyright 2017-2021 AT&T Intellectual Property. All rights reserved.
+#  Modification Copyright 2021. Nordix Foundation.
 # ================================================================================
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -21,9 +22,9 @@
 # OS upgrades
 
 echo "Uninstall docker-py and reinstall docker."
-pip uninstall -y docker-py
-pip uninstall -y docker
-pip install -U docker==2.7.0
+pip3 uninstall -y docker-py
+pip3 uninstall -y docker
+pip3 install -U docker
 
 sudo apt-get -y install libxml2-utils