Pinned repositories

Stream: general

[Joseph Myers]

At the top of https://github.com/leanprover-community the mathlib(3) and community Lean 3 repositories appear as pinned repositories. I'd have expected mathlib4 to be pinned now, but not anything to do with Lean 3.

[Eric Wieser]

I edited it to be mathlib4, MIL, mathport, and lean-liquid