`bazel run` should run in bazel env working directory

# 🚀 feature request

### Relevant Rules
This is meant to change the behavior of `py_binary`

### Description
Currently if you run a binary with `bazel run` then the working directory will be the sandboxed bazel directory. This behavior is inconsistent with other implementations, for example in `rules_go` it is set like this https://github.com/bazel-contrib/rules_go/blob/b60f4475e3d97431318da1a0a81752a8884e6994/go/tools/go_bin_runner/main.go#L250

### Describe the solution you'd like

`bazel run` should use the `BUILD_WORKING_DIRECTORY` environment variable to set the working directory.

### Describe alternatives you've considered

You can do this hack where you add `--run_under="cd $PWD &&"` to the command but it only works on POSIX systems and you basically have to know the trick to have the command do what you might expect

Start at the py_binary implementation involved in bazel run and compare its behavior with the rules_go runner linked in the issue. Verify how BUILD_WORKING_DIRECTORY is exposed, then confirm that bazel run uses it as the working directory rather than the sandbox directory.

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