Odd grpc error

From John in tilt slack-

Hey, I'm having trouble with my setup and I'm not sure how to debug it. Basically I'm seeing the error

 Build Failed: failed to dial gRPC: unable to upgrade to h2c, received 404

when running a docker_build, however running tilt docker --built . works fine. I am using minikube in rootless podman so I suspect there is something about that setup which is causing issues. Here is the output of doctor:

 Tilt: v0.33.20, built 2024-09-03
 System: linux-amd64
 ---
 Docker
 - Host: unix:///run/user/1000/podman/podman.sock
 - Server Version: 5.2.2
 - API Version: 1.41
 - Builder: 2
 ---
 Kubernetes
 - Env: minikube
 - Context: minikube
 - Cluster Name: minikube
 - Namespace: default
 - Container Runtime: containerd
 - Version: v1.30.0
 - Cluster Local Registry: none
 - 

Usually i'd expect tilt to detect that podman doesn't support buildkits grpc protocol and fallback to the rest protocol.

Might be related to recent updates to docker client libs

Current workaround is to set DOCKER_BUILDKIT=0 in the env

Start by reproducing the reported docker_build failure with minikube and rootless Podman, then compare it with docker --built . and the DOCKER_BUILDKIT=0 workaround. Done means the docker_build path handles this environment without requiring that workaround, while preserving the existing behavior.