chore: Normalize case of keywords in Dockerfiles

Author: jpmckinney

Dockerfile_django

@@ -1,4 +1,4 @@
-FROM python:3.11 as build-stage
+FROM python:3.11 AS build-stage
 
 COPY requirements.txt /tmp/requirements.txt
 RUN pip install --no-cache-dir -r /tmp/requirements.txt

Dockerfile_static

@@ -1,4 +1,4 @@
-FROM python:3.11 as build-stage
+FROM python:3.11 AS build-stage
 
 COPY requirements.txt /tmp/requirements.txt
 RUN pip install --no-cache-dir -r /tmp/requirements.txt
@@ -10,7 +10,7 @@ ENV DJANGO_ENV=production
 
 RUN python manage.py collectstatic --noinput -v2
 
-FROM nginxinc/nginx-unprivileged:latest as production-stage
+FROM nginxinc/nginx-unprivileged:latest AS production-stage
 USER root
 COPY --from=build-stage --chown=nginx:root /workdir/static /usr/share/nginx/html/static
 COPY --chown=nginx:root default.conf /etc/nginx/conf.d/default.conf