Packages - force python 3.9 (#5206)

* specify python 3.9

* now support 12 too

* rmove 12

* change deps

* add dedicated wheel install

* add dev headers (for rappidfuzz)

.pkgr.yml

@@ -19,8 +19,9 @@ before:
   - contrib/packager.io/before.sh
 dependencies:
   - curl
-  - python3
-  - python3-venv
+  - python3.9
+  - python3.9-venv
+  - python3.9-dev
   - python3-pip
   - python3-cffi
   - python3-brotli

contrib/packager.io/functions.sh

@@ -235,6 +235,7 @@ function update_or_install() {
 
   # Run update as app user
   echo "# Updating InvenTree"
+  sudo -u ${APP_USER} --preserve-env=$SETUP_ENVS bash -c "cd ${APP_HOME} && pip install wheel"
   sudo -u ${APP_USER} --preserve-env=$SETUP_ENVS bash -c "cd ${APP_HOME} && invoke update --no-frontend | sed -e 's/^/# inv update| /;'"
 
   # Make sure permissions are correct again

contrib/packager.io/postinstall.sh

@@ -23,7 +23,7 @@ export DATA_DIR=${APP_HOME}/data
 export SETUP_NGINX_FILE=${SETUP_NGINX_FILE:-/etc/nginx/sites-enabled/inventree.conf}
 export SETUP_ADMIN_PASSWORD_FILE=${CONF_DIR}/admin_password.txt
 export SETUP_NO_CALLS=${SETUP_NO_CALLS:-false}
-export SETUP_PYTHON=${SETUP_PYTHON:-python3}
+export SETUP_PYTHON=${SETUP_PYTHON:-python3.9}
 # SETUP_DEBUG can be set to get debug info
 # SETUP_EXTRA_PIP can be set to install extra pip packages
 # SETUP_PYTHON can be set to use a different python version