feat: added eulerian path to graph

[jeevanpranav02]

Description

Implementation of Eulerian Path from the issue #344

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• I ran bellow commands using the latest version of rust nightly.
• I ran cargo clippy --all -- -D warnings just before my last commit and fixed any issue that was found.
• I ran cargo fmt just before my last commit.
• I ran cargo test just before my last commit and all tests passed.
• I checked COUNTRIBUTING.md and my code follows its guidelines.

I hope this closes the issue for Euclerian Path.
I would request if you can add label:hactoberfest-accepted to this PR if applicable. :)

[siriak]

Please check why cargo clippy fails

[jeevanpranav02]

I checked the warning, and when I ran cargo clippy --all -- -D warnings there was no error on my PC. However, here, Clippy suggested a change, which I made. If there are any other changes you'd like me to make, please feel free to ask. I'll be happy to do it.

[siriak]

Looks good, thanks!

[jeevanpranav02]

Thanks @siriak Can you please add label:hactoberfest-accepted : )