DO NOT MERGE ANYWHERE - Update ub-conscrypt to use main branch.

Bug: b/289400079
Change-Id: I1089f1fdc5c9bbd854076b1e405da055f51cba30
diff --git a/default.xml b/default.xml
index ea41e40..8a91a3c 100644
--- a/default.xml
+++ b/default.xml
@@ -5,7 +5,7 @@
            fetch=".."
            review="https://android-review.googlesource.com/" />
 
-  <default revision="master"
+  <default revision="main"
            remote="aosp"
            sync-j="4" />