Updates the installer library to be static in the final image, saving the installers into Git and curl-ing the correct revision

docker-builders/Dockerfile.pikepdf

@@ -7,12 +7,17 @@
 # Default to pulling from the main repo registry when manually building
 ARG REPO="paperless-ngx/paperless-ngx"
 
+# This does nothing, except provide a name for a copy below
 ARG QPDF_VERSION
 FROM --platform=$BUILDPLATFORM ghcr.io/${REPO}/builder/qpdf:${QPDF_VERSION} as qpdf-builder
 
-# This does nothing, except provide a name for a copy below
-
-FROM python:3.9-slim-bullseye as main
+#
+# Stage: builder
+# Purpose:
+#  - Build the pikepdf wheel
+#  - Build any dependent wheels which can't be found
+#
+FROM python:3.9-slim-bullseye as builder
 
 LABEL org.opencontainers.image.description="A intermediate image with pikepdf wheel built"
 
@@ -100,3 +105,14 @@ RUN set -eux \
     && apt-get -y purge ${BUILD_PACKAGES} \
     && apt-get -y autoremove --purge \
     && rm -rf /var/lib/apt/lists/*
+
+#
+# Stage: package
+# Purpose: Holds the compiled .whl files in a tiny image to pull
+#
+FROM alpine:3.17 as package
+
+WORKDIR /usr/src/wheels/
+
+COPY --from=builder /usr/src/wheels/*.whl ./
+COPY --from=builder /usr/src/wheels/pkg-list.txt ./