Pre-create app.log file to fix logging configuration error

Dockerfile

@@ -1,5 +1,5 @@
-# Use official Python 3.9 image
-FROM python:3.9
+# Use official Python 3.1 image
+FROM python:3.2
 
 # Set working directory to /app (root of the repository)
 WORKDIR /app
@@ -13,8 +13,9 @@ RUN pip install --no-cache-dir --upgrade -r requirements.txt loguru
 # Copy the entire project
 COPY . /app
 
-# Create user if it doesn't exist, then switch to it
+# Create user if it doesn't exist, then switch to it and pre-create log file
 RUN id -u user &>/dev/null || useradd -m -u 1000 user
+RUN mkdir -p /home/user && touch /home/user/app.log && chown user:user /home/user/app.log
 USER user
 ENV HOME=/home/user \
     PATH=/home/user/.local/bin:$PATH