Invalid repository name when running a local docker action

[cedrickring]

act Version: 0.2.5
OS: macOS & Windows

When running a local docker action from a different directory, the docker build command receives an invalid repository name:

Command: docker build -t act-Users-cedrickring-golang-action:latest /Users/cedrickring/golang-action
Output: Error: invalid reference format: repository name must be lowercase

Steps to reproduce

1. Clone cedrickring/golang-action
2. Create a different directory with a .github/workflows/workflow.yaml and reference the action with ../relative/path/to/golang-action
3. Run act

[cedrickring]

I don't really know if Github allows this but this happened to me while trying to create a workaround for #128.

[cplee]

fixed on master. will cut a new release later today.