Firebase Unity SDK Samples page does not correctly link to CONTRIBUTING.md

[rwhogg]

What Happened?
On the Unity SDK Samples page, the CONTRIBUTING.md link takes you to https://github.com/firebase/quickstart-unity/tree/master/contributing.md , which 404's.

What Did You Expect to Happen
It should take you to https://github.com/firebase/quickstart-unity/blob/master/CONTRIBUTING.md

Note that the link is correct in the source repo, it's only on firebaseopensource.com that it links incorrectly.

[thatfiredev]

Thanks for reporting this @rwhogg

It seems like that problem happens with projects that use relative paths (eg. /CONTRIBUTING.md) on their README.
I think that problem could/should be corrected on the firebaseopensource.com side, but I'm not very familiar with this codebase. I'll try to figure out a way to fix that

[thatfiredev]

cc: @lupas
In case you have any suggestions :)