Node segment shows up all the time if node is in the path.

[duckpuppy]

Describe the bug
If node is in the current executable search path, the node segment shows the node version even if not in a node project.

To Reproduce
Steps to reproduce the behavior:

1. Add node executable to system search path
2. Enable node segment in powerline-go

Expected behavior
Node segment should only show up when in a node project (ie. when there's also a package version)

Environment (please complete the following information):

• OS: macOS Monterey
• Architecture: intel
• Shell: zsh

Additional context
Bug was added with this commit: 14bfc26

The segment should not be visible unless there's also a package version to display.