### Check existing issues - [x] I've verified that this bug isn't described by any existing issues. ### Bug description Recently I'm getting this additional warning output ### Steps to reproduce `rockcraft pack` ### Environment concierge prepare -p k8s ### rockcraft.yaml ```yaml --- name: gubernator version: 3.0.0 summary: High-performance, distributed rate-limiting service description: | Gubernator is a high-performance, distributed rate-limiting service. license: Apache-2.0 platforms: {amd64: null, arm64: null} base: ubuntu@24.04 parts: go-deps: plugin: nil build-packages: - golang-go gubernator: plugin: go source: https://github.com/gubernator-io/gubernator.git source-type: git # The tip of the v3.0 branch fails the health check # source-branch: v3.0 # A known good revision from v3.0 branch from June 2024 source-commit: 2903b1b566dc9beab322e37ecef4aff50c1a7a97 stage-packages: - ca-certificates after: - go-deps services: gubernator: override: replace startup: enabled command: /bin/gubernator environment: GUBER_TRACING_LEVEL: DEBUG GUBER_HTTP_ADDRESS: 0.0.0.0:80 GUBER_GRPC_ADDRESS: 0.0.0.0:81 on-success: shutdown on-failure: shutdown on-check-failure: online: shutdown checks: online: override: replace exec: # The healthcheck binary is provided by gubernator, it uses same env vars as the daemon command: /bin/healthcheck period: 3s ``` ### Log output ```shell Skipping prime for pebble (already ran)/snap/rockcraft/4238/lib/python3.12/site-packages/pydantic/main.py:464: UserWarning: Pydantic serializer warnings: PydanticSerializationUnexpectedValue(Defaulting to left to right union serialization - failed to get discriminator value for tagged union serialization [input_value=ExecCheck(override='repla...None, working_dir=None)), input_type=ExecCheck]) return self.__pydantic_serializer__.to_python( ```