### Bug Description One can set verbosity level either via CLI with a flag `--verbosity=foo` or with a corresponding environment variable `SNAPCRAFT_VERBOSITY_LEVEL=foo`. Doing the latter no longer works, and the default verbosity level is used instead. Other environment variables seem unaffected (like `SNAPCRAFT_{BUILD_INFO,UA_TOKEN}`). ### To Reproduce Install `snapcraft` on latest/edge (tested on 10677 (amd64) and 10926 (riscv64)) Set `SNAPCRAFT_VERBOSITY_LEVEL=verbose` Invoke `snapcraft` for any snap Using `--verbosity=verbose` works as expected. The behavior is as expected in my test-cases using latest/stable. ### Environment Ubuntu ~23.10 on AMD64 and RISCV64. On RISCV64, it's just the simple preinstalled server image for the VisionFive2. In my test cases I was building ubuntu-image and serial-vault-snap. ### snapcraft.yaml ```shell Any snapcraft.yaml should suffice ``` ### Relevant log output ```shell ubuntu@ubuntu:~/ubuntu-image$ env | grep SNAPCRAFT_VERBOSITY SNAPCRAFT_VERBOSITY_LEVEL=verbose ubuntu@ubuntu:~/ubuntu-image$ snapcraft Attached specified UA token Detached specified UA token Generated snap metadata Generated snap manifest Lint OK: - classic: Snap confinement is set to classic. Lint warnings: - library: libbrotlienc.so.1: unused library 'usr/lib/riscv64-linux-gnu/libbrotlienc.so.1.0.9'. (https://snapcraft.io/docs/linters-library) Created snap package ubuntu-image_3.3_riscv64.snap compare: ubuntu@ubuntu:~/ubuntu-image$ snapcraft clean; snapcraft --verbosity=verbose Cleaned build provider Starting snapcraft Logging execution to '/home/ubuntu/.local/state/snapcraft/log/snapcraft-20240308-154549.239864.log' Starting snapcraft Logging execution to '/home/ubuntu/.local/state/snapcraft/log/snapcraft-20240308-154549.239864.log' Running on riscv64 for riscv64 Launching instance... Creating instance from base instance Starting instance Starting snapcraft Logging execution to '/root/.local/state/snapcraft/log/snapcraft-20240308-155237.920470.log' Starting snapcraft Logging execution to '/root/.local/state/snapcraft/log/snapcraft-20240308-155237.920470.log' Running on riscv64 for riscv64 Initializing parts lifecycle {snip} Installing build-packages Installing build-snaps Pulling ubuntu-image Fetching stage-packages Building ubuntu-image :: + ins_bin=/root/parts/ubuntu-image/install/bin/ :: + mkdir -p /root/parts/ubuntu-image/install/bin/ :: + CGO_ENABLED=0 {snip} ``` ### Additional context _No response_