Update vote service to python:3.11

Signed-off-by: Michael Irwin <mikesir87@gmail.com>

vote/Dockerfile

@@ -1,20 +1,19 @@
 # Using official python runtime base image
-FROM python:3.9-slim
+FROM python:3.11-slim
 
 # add curl for healthcheck
-RUN apt-get update \
-    && apt-get install -y --no-install-recommends \
-    curl \
-    && rm -rf /var/lib/apt/lists/*
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends curl && \
+    rm -rf /var/lib/apt/lists/*
 
 # Set the application directory
-WORKDIR /app
+WORKDIR /usr/local/app
 
 # Install our requirements.txt
-COPY requirements.txt /app/requirements.txt
-RUN pip install -r requirements.txt
+COPY requirements.txt ./requirements.txt
+RUN pip install --no-cache-dir -r requirements.txt
 
-# Copy our code from the current folder to /app inside the container
+# Copy our code from the current folder to the working directory inside the container
 COPY . .
 
 # Make port 80 available for links and/or publish