Updated security.yml to python 3.9

Updated security.yml to python 3.9, the same as the current RedBorder NG version.

.github/workflows/security.yml

@@ -17,13 +17,13 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v2
 
-    - name: Set up Python 3.8 and pip
+    - name: Set up Python 3.9 and pip
       run: |
         sudo add-apt-repository ppa:deadsnakes/ppa -y
         sudo apt update
-        sudo apt install -y python3.8 python3.8-distutils
+        sudo apt install -y python3.9 python3.9-distutils
         curl -s https://bootstrap.pypa.io/get-pip.py -o get-pip.py
-        sudo python3.8 get-pip.py
+        sudo python3.9 get-pip.py
 
     - name: Install safety for security checks
       run: |