build: separate deploy jobs in deploy build stage (#5621)

Currently every deployment runs in a single Travis job concurrently. This messes up the logs and it's also hard to see what actually runs at all.

The different deployment jobs should run concurrently in the deploy build stage.

scripts/ci/travis-script.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+
+# Script that runs in every Travis CI container. The script is responsible for delegating
+# to the different scripts that should run for specific Travis jobs in a build stage.
+
+# The script should immediately exit if any command in the script fails.
+set -e
+
+# Go to project directory
+cd $(dirname $0)/../..
+
+if [[ -z "$TRAVIS" ]]; then
+  echo "This script can only run inside of Travis build jobs."
+  exit 1
+fi
+
+if [[ "${MODE}" ]]; then
+  ./scripts/ci/travis-testing.sh
+elif [[ "${DEPLOY_MODE}" ]]; then
+  ./scripts/ci/travis-deploy.sh
+fi