[infra] Update recipes.cfg to use main branch

Change-Id: I4cd34eec09775f39421c6077d3669df99dad57d1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/442321
Reviewed-by: Ravi Mistry <rmistry@google.com>
Commit-Queue: Eric Boren <borenet@google.com>
1 file changed