Minor tool-tip correction

[kf6nux]

Makes tool-tip consistent with class description, and consistent with "Working Files" tool-tips.

Helps avoid new-user confusion (a new user might think "Collapse" collapses the work-space rather than all the contained folders in the work-space).

[msftclas]

Hi @kf6nux, I'm your friendly neighborhood Microsoft Pull Request Bot (You can call me MSBOT). Thanks for your contribution!

This seems like a small (but important) contribution, so no Contribution License Agreement is required at this point. Real humans will now evaluate your PR.

TTYL, MSBOT;

[bpasero]

👍