Update Dockerfile to new repository URL, add dependencies

- Debian stretch has moved to archive.debian.org as of late April 2023
- Fix a version conflict with libssl1.1
- Add python3, as required by the rust build script

Relates to #72

Dockerfile

@@ -9,14 +9,14 @@ LABEL maintainer "Solana Maintainers"
 #RUN gpg --no-tty --keyserver hkp://pgp.mit.edu --recv 0x2D2CEF1034921684
 
 # Install build dependencies of rust.
-# First, Update the apt's source list and include the sources of the packages.
-RUN grep deb /etc/apt/sources.list | \
- sed 's/^deb/deb-src /g' >> /etc/apt/sources.list
+# Replace the original sources.list with archive.debian.org, since as of April 2023, Debian stretch has been moved there from the main repository
+RUN echo "deb http://archive.debian.org/debian stretch main contrib non-free" > /etc/apt/sources.list
 
 # Install compiler, python and subversion.
 RUN apt-get update && \
  apt-get install -y \
  --no-install-recommends \
+ --allow-downgrades \
  ca-certificates gnupg \
  build-essential \
  python \
@@ -29,7 +29,9 @@ RUN apt-get update && \
  clang \
  ssh \
  openssl \
- libssl-dev && \
+ libssl1.1=1.1.0l-1~deb9u1 \
+ libssl-dev \
+ python3 && \
  rm -rf /var/lib/apt/lists/* && \
  apt-get update && \
  apt-get install -y pkg-config