staging lsb-release in python part make the part fail

[Guillaume Beuzeboc]

Staging the apt package lsb-release in python part make the build of the part fail with the following message:

Pulling my-part
+ snapcraftctl pull
Building my-part
+ snapcraftctl build
+ python3 -m venv /root/parts/my-part/install
Error: Command '['/root/parts/my-part/install/bin/python3', '-Im', 'ensurepip', '--upgrade', '--default-pip']' returned non-zero exit status 1.
Failed to build 'my-part'.

The snapcraft.yaml is:

  name: my-snap-name
  base: core20
  version: '0.1'
  summary: text
  description: |
    more text

  grade: devel # must be 'stable' to release into candidate/stable channels
  confinement: devmode # use 'strict' once you have the right plugs and slots

  parts:
    my-part:
      plugin: python
      python-packages: [numpy]
      stage-packages: [lsb-release]
  apps:
    my-snap-name:
      command: bin/python3

Calling snapcraft over it causes the issue.
Removing ${SNAPCRAFT_PART_INSTALL}/bin from the PATH seems to solve the issue, but this is hardcoded in the plugin

[Guillaume Beuzeboc (gbeuzeboc)]

Adding a second part with the nil plugin simple staging lsb-release produces the same error if built before but not if built after.