Run Docker builder as root

Author: adilhusain-s

python-versions/Dockerfile

@@ -15,6 +15,9 @@ ARG TARGETARCH
 ARG PYTHON_VERSION
 ARG ACTIONS_PYTHON_VERSIONS
 
+# The upstream PowerShell image switches to a non-root user; switch back so apt can write system files.
+USER root
+
 # Set environment variables
 ENV DEBIAN_FRONTEND=noninteractive \
     CC=gcc \