Fails with space in directory name

When using git-remote-codecommit to fetch or push code (or presumably any other command), I get this error:

```
fatal: 'remote-codecommit' appears to be a git command, but we were not
able to execute it. Maybe git-remote-codecommit is broken?
make: *** [git-push] Error 128
```

The problem is that my directory had a space:

/Users/myname/Documents/Coding/AWS CDK/myproject

When I removed the space from "AWS CDK" directory, it worked.

Please fix this package to support spaces in directory names.

(This is on macOS.)