No progress callbacks on git push and pull

[chris-addison]

Prerequisites

• Be sure to run with tracing enabled to capture runtime details in the log file
• Include the log file in the PR.
  • On Windows, the extension log file is at %LOCALAPPDATA%\GitHubUnity\github-unity.log
  • On macOS, the extension log file is at ~/Library/Logs/GitHubUnity/github-unity.log
  • On linux, the extension log file is at ~/.local/share/GitHubUnity/github-unity.log

Description

When calling git pull or push, there is only progress events at 0% and 100%. Ideally, there should be some way to expose the cli progress info into the api.

Steps to Reproduce

1. Start a git pull/push with a `.Progress(p => Debug.Log(p.Percentage))
2. Observe just 0.0 and 1.0

Expected behavior: More values between 0 and 1

Actual behavior: Only 0 and 1

Reproduces how often: 100%

Additional Information

Any additional information, configuration or data that might be necessary to reproduce the issue.