Update mysql port in Tests Pipeline

Author: kkamara

.github/workflows/build.yml

@@ -51,6 +51,8 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install -r requirements.txt
+    - name: Prepare Env Variables
+      run: sed -i "s/3306/${{ job.services.mysql.ports['3306'] }}/g" .env.testing
     - name: Create environment file
       run: cp .env.testing .env
     - name: Run Tests