Run tests directly from the Makefile

Contributes to: https://github.com/alphagov/notifications-manuals/issues/9

Precedent: https://github.com/alphagov/notifications-admin/pull/3897

scripts/run_tests.sh

@@ -1,38 +0,0 @@
-#!/bin/bash
-#
-# Run project tests
-#
-# NOTE: This script expects to be run from the project root with
-# ./scripts/run_tests.sh
-
-set -o pipefail
-
-function display_result {
-  RESULT=$1
-  EXIT_STATUS=$2
-  TEST=$3
-
-  if [ $RESULT -ne 0 ]; then
-    echo -e "\033[31m$TEST failed\033[0m"
-    exit $EXIT_STATUS
-  else
-    echo -e "\033[32m$TEST passed\033[0m"
-  fi
-}
-
-if [[ -z "$VIRTUAL_ENV" ]] && [[ -d venv ]]; then
-  source ./venv/bin/activate
-fi
-
-make test-requirements
-display_result $? 1 "Requirements check"
-
-flake8 .
-display_result $? 1 "Code style check"
-
-isort --check-only ./app ./tests
-display_result $? 2 "Import order check"
-
-# run with four concurrent threads
-py.test -n4 -v --maxfail=10
-display_result $? 2 "Unit tests"