Merge juju-lint:fix-core20 into juju-lint:master

[Gabriel Cocenza]

Fix to have the snap working on bionic and jammy.

core20 need to have python libs on stage-packages in order to work
on jammy and bionic series.

When using core20, snapcraft reduces snap sizes by not staging anything found in the base snap, unless explicitly listed in the stage-packages. This unfortunately cause issues with python3 classic-mode. [0]

[0] https://forum.snapcraft.io/t/trouble-bundling-python-with-classic-confinement-in-core20-4-0-4/18234

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[Eric Chen (eric-chen)]

review: Approve

[Martin Kalcok (martin-kalcok)]

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision d8625c2cf2cb12a09d3a2f424ef9ea01ade97770

diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index 555e9af..69b6b71 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -22,6 +22,20 @@ parts:
       - requirements.txt
     source: .
     source-type: git
+    # Classic core20 snaps require staged python.
+    python-packages: [pip, setuptools, wheel]
+    stage-packages:
+      - libpython3-stdlib
+      - libpython3.8-minimal
+      - libpython3.8-stdlib
+      - python3.8-minimal
+      - python3-distutils
+      - python3-minimal
+      - python3-pkg-resources
+      - python3-pip
+      - python3-setuptools
+      - python3-venv
+      - python3-wheel
     override-build: |
         snapcraftctl build
         echo "Version: $(python3 setup.py --version)"