Switch Binaryen branch from master to main
Switch Binaryen branch from master to main

The Binaryen project has switched its default branch.

Change-Id: Ic3ec1a9120940a23700a0ed80c4fed0891579811
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/356120
Auto-Submit: Alon Zakai <637369de62879ecfe9a8f34fb07ea9da35713965@google.com>
Reviewed-by: Sam Clegg <4504a65e6a180f18042ae97f363f5ae49cc5c461@google.com>
Reviewed-by: Thomas Lively <6d0eb04eded5b535c7fb3ea181fdac9b5e798a46@google.com>
Reviewed-by: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>
Commit-Queue: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>

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