Update setting conda reqs in README.md

Please review these guidelines to help with the review process:

[ ] Have you provided a meaningful PR description?
[ ] Have you added a test, a reproducer, or a reference to an issue with a reproducer?
[ ] Have you tested your changes locally for CPU and GPU devices?
[ ] Have you made sure that new changes do not introduce compiler warnings?
[ ] If this PR is a work in progress, are you filing the PR as a draft?
[ ] Have you organized your commits logically and ensured each can be built by itself?

intel / mlir-extensions