Update 'dnf' installation step with cherry-pick (#330) (#331)

* Revert "Add update statement to manylinux Dockefile instructions. (#329)"

This reverts commit a290efb.

* Remove installation of gnupg1 package. No longer available for installation from distributed repository. (#330)

Author: mc-nv

tools/gen_ort_dockerfile.py

@@ -142,13 +142,11 @@ def dockerfile_for_linux(output_file):
 ENV PYTHON_BIN_PATH=${PYBIN}/python${PYVER} \
     PATH=${PYBIN}:${PATH}
 
-RUN dnf update && \\
-    dnf install -y \\
+RUN dnf install -y \\
         ca-certificates \\
         curl \\
         git \\
         gnupg \\
-        gnupg1 \\
         openssl-devel \\
         python3-pip \\
         wget \\