Improve organization of CI workflow scripts and pip requirements (#45037)

.github/workflows/bin/generate_spack_yaml_containerize.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+    (echo "spack:" \
+&&   echo "  specs: []" \
+&&   echo "  container:" \
+&&   echo "    format: docker" \
+&&   echo "    images:" \
+&&   echo "      os: \"${SPACK_YAML_OS}\"" \
+&&   echo "      spack:" \
+&&   echo "        ref: ${GITHUB_REF}") > spack.yaml