make testrunner.sh in host-tools directory

[kittenkamala]

Create a bash script with commands (like below) that hosts can use to run the testing and reporting process in one step inside the host-tools directory

This one is for running tests and reporting once the test runner is already set up.

#script to update git, run tests, make report and clean up files once test runner is configured.
cd /home/wptestrunner/phpunit-test-runner/ #file path to test runner directory, change if needed
git pull
git checkout master
source .env #credentials must already be saved in env file
php prepare.php
php test.php
php report.php #report bot must already be configured
php cleanup.php