chore(*): update Sauce Connect from 4.4.12 to 4.5.1

Sauce Connect 4.5.0 fixes "a major bug in connection state logic that caused
clients to exit prematurely".
See https://wiki.saucelabs.com/display/DOCS/Sauce+Connect+Proxy+Change+Logs
This will possibly improve the stability of our test runs.

Closes angular#16730

Author: mgol

lib/saucelabs/start_tunnel.sh

@@ -11,7 +11,7 @@ set -e
 # Curl and run this script as part of your .travis.yml before_script section:
 # before_script:
 #   - curl https://gist.github.com/santiycr/5139565/raw/sauce_connect_setup.sh | bash
-SC_VERSION="4.4.12"
+SC_VERSION="4.5.1"
 CONNECT_URL="https://saucelabs.com/downloads/sc-$SC_VERSION-linux.tar.gz"
 CONNECT_DIR="/tmp/sauce-connect-$RANDOM"
 CONNECT_DOWNLOAD="sc-$SC_VERSION-linux.tar.gz"