[Docs]: Update GitHub issue template

[sdavids]

Describe what's incorrect/missing in the documentation

react-router/package.json

Line 119 in 807f4a2

"node": ">=20.0.0"

StackBlitz does not support Node 20/22.

So you should remove its mention in the GitHub issue template:

🥇 Link to a StackBlitz environment

[brophdawg11]

It's super unfortunate that stackblitz is lagging behind here - but despite the warnings in the console node 18 mostly works just fine for bug reproductions -- so I think this should stay.

Removing it would raise the barrier to a good bug report and will just result in a bunch of copy/pasted non-runnable code. A working reproduction is orders of magnitude more helpful to us as maintainers than copy/pasted code...