Use the ubuntu keyserver to retrieve the edX PPA key.

We already do this in the common role but not in bootstrap or abbey roles.

(cherry picked from commit b78c0487)

util/install/ansible-bootstrap.sh

@@ -48,7 +48,7 @@ PYTHON_BIN="${VIRTUAL_ENV}/bin"
 ANSIBLE_DIR="/tmp/ansible"
 CONFIGURATION_DIR="/tmp/configuration"
 EDX_PPA="deb http://ppa.edx.org precise main"
-EDX_PPA_KEY_SERVER="hkp://pgp.mit.edu:80"
+EDX_PPA_KEY_SERVER="keyserver.ubuntu.com"
 EDX_PPA_KEY_ID="B41E5E3969464050"
 
 cat << EOF

util/vpc-tools/abbey.py

@@ -331,7 +331,7 @@ VIRTUAL_ENV_VERSION="15.0.2"
 PIP_VERSION="8.1.2"
 SETUPTOOLS_VERSION="24.0.3"
 EDX_PPA="deb http://ppa.edx.org precise main"
-EDX_PPA_KEY_SERVER="hkp://pgp.mit.edu:80"
+EDX_PPA_KEY_SERVER="keyserver.ubuntu.com"
 EDX_PPA_KEY_ID="B41E5E3969464050"
 
 cat << EOF