supervisor: Lock dependencies to Python version it was built with/ins…

…talls to (#36800)

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Uses a similar approach to #28955 to express dependencies against
specific python version, since this is coupled at build time, avoiding
problems when a new, later python version is released, and the correct
setuptools is no longer installed via `py3-setuptools`.

- fixes #36785

supervisor.yaml

@@ -1,21 +1,24 @@
 package:
   name: supervisor
   version: 4.2.5
-  epoch: 6
+  epoch: 7
   description: Supervisor process control system for Unix (supervisord)
   copyright:
     - license: BSD-3-Clause
   dependencies:
     runtime:
-      - py3-setuptools
+      - py${{vars.py-version}}-setuptools
       - supervisor-config
 
+vars:
+  py-version: 3.12
+
 environment:
   contents:
     packages:
       - busybox
-      - py3-pip
-      - python3
+      - py${{vars.py-version}}-pip
+      - python-${{vars.py-version}}
 
 pipeline:
   - uses: git-checkout
@@ -26,7 +29,7 @@ pipeline:
 
   - name: Python Install
     runs: |
-      sitepackages=$(python3 -c 'import site; print(site.getsitepackages()[0])')
+      sitepackages=$(python${{vars.py-version}} -c 'import site; print(site.getsitepackages()[0])')
       concatenated_path="${{targets.destdir}}${sitepackages}"
 
       echo "sitepackages=$sitepackages"
@@ -88,7 +91,7 @@ subpackages:
     description: Precompiled Python bytecode for supervisor
     pipeline:
       - runs: |
-          sitepackages=$(python3 -c 'import site; print(site.getsitepackages()[0])')
+          sitepackages=$(python${{vars.py-version}} -c 'import site; print(site.getsitepackages()[0])')
           destdir_concatenated_path="${{targets.destdir}}${sitepackages}"
           subpkg_concatenated_path="${{targets.subpkgdir}}${sitepackages}"
           mkdir -p "${subpkg_concatenated_path}/supervisor/__pycache__/"