Environment is being set for classic snaps

[sergiusens]

Bug Description

The top level environment with LD_LIBRARY_PATH and PATH is being set for snaps set to classic confinement when using core22 as a base.

This can cause application crashes. In previous bases we made use of the command-chain and did not export these environment variables when going classic

To Reproduce

• Create a core22 base snap
• Set confinement: classic
• Run snapcraft prime --shell-after
• Run grep -A3 '^environment:' ../prime/meta/snap.yaml to verify that the wrong keywords are there

Environment

N/A

snapcraft.yaml

name: snapcraft
base: core22
summary: easily create snaps
description: |
    Snapcraft aims to make upstream developers' lives easier and as such is not
    a single toolset, but instead is a collection of tools that enable the
    natural workflow of an upstream to be extended with a simple release step
    into Snappy.
adopt-info: snapcraft
confinement: classic
license: GPL-3.0
assumes:
  - snapd2.43

apps:
  snapcraft:
    environment:
      PATH: "$SNAP/libexec/snapcraft:/snap/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
      # https://github.com/lxc/pylxd/pull/361
      PYLXD_WARNINGS: "none"
    command: bin/python $SNAP/bin/snapcraft
    completer: snapcraft-completion
....

Relevant log output

$ cat /snap/snapcraft/current/meta/snap.yaml 
name: snapcraft
version: 7.4.0.post7+gitd67a3d5b
summary: easily create snaps
description: |
  Snapcraft aims to make upstream developers' lives easier and as such is not
  a single toolset, but instead is a collection of tools that enable the
  natural workflow of an upstream to be extended with a simple release step
  into Snappy.
license: GPL-3.0
architectures:
- amd64
base: core22
assumes:
- snapd2.43
apps:
  snapcraft:
    command: bin/python $SNAP/bin/snapcraft
    completer: snapcraft-completion
    environment:
      PATH: $SNAP/libexec/snapcraft:/snap/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
      PYLXD_WARNINGS: none
confinement: classic
grade: devel
environment:
  LD_LIBRARY_PATH: ${SNAP_LIBRARY_PATH}${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}:$SNAP/lib:$SNAP/usr/lib:$SNAP/usr/lib/x86_64-linux-gnu
  PATH: $SNAP/usr/sbin:$SNAP/usr/bin:$SNAP/sbin:$SNAP/bin:$PATH
hooks:
  configure:
    environment:
      PATH: $SNAP/bin

Additional context

No response