Add Peter Collingbourne <pcc@google.com> to CONTRIBUTORS
diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 6b605d7..bf413f8 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -29,6 +29,7 @@
 Håkan L. S. Younes <hyounes@google.com>
 Ivan Penkov <ivanpe@google.com>
 Michael Tanner <michael@tannertaxpro.com>
+Peter Collingbourne <pcc@google.com>
 romange <romange@users.noreply.github.com>
 Sergiu Dotenco <sergiu.dotenco@th-nuernberg.de>
 Shinichiro Hamaji <hamaji@google.com>