Update src/compliance to point to main branches instead of release.

BUG=b/245375131
TEST=None
RELEASE_NOTE=None

Change-Id: I8935086c5c6725957152666251e638f643567e1c
Reviewed-on: https://cos-review.googlesource.com/c/cos/manifest/+/36869
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Tested-by: Arnav Kansal <rnv@google.com>

external_full.xml

diff --git a/external_full.xml b/external_full.xml
index 219e9b3..6277ba0 100644
--- a/external_full.xml
+++ b/external_full.xml
@@ -90,7 +90,8 @@
   <project path="src/platform/vboot_reference"
            name="third_party/platform/vboot_reference" />
   <project path="src/compliance"
-           name="cos/compliance" />
+           name="cos/compliance"
+           revision="refs/heads/main-R97" />
   <project path="src/repohooks"
            name="cos/repohooks"
            revision="refs/heads/master" />