Add tree data structures in rust language

[rohansen856]

Is your feature request related to a problem? Please describe.
I see that there is no rDSA in rust languuage in this repo. I would like too add Tree data structures in Rust

Describe the solution you'd like
I will add Basic tree structure DSA in this repo

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[rohansen856]

Can you please assign this to me under hacktoberfest label?

[rohansen856]

I have already solved this issue under PR #439. Thank you.

[Kirti-Pant]

hey @rohansen856, can you assign this issue to me?