runner: Remove redundant check for (D)TLS 1.3 in test code

useTrafficSecret is only called for 1.3.

Bug: 42290594
Change-Id: I842b734c6314da4910607dc62994c5236aca302e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/72567
Reviewed-by: Nick Harper <nharper@chromium.org>
Commit-Queue: David Benjamin <davidben@google.com>

ssl/test/runner/conn.go

diff --git a/ssl/test/runner/conn.go b/ssl/test/runner/conn.go
index 440f630..525f85f 100644
--- a/ssl/test/runner/conn.go
+++ b/ssl/test/runner/conn.go
@@ -270,7 +270,8 @@
 		hc.cipher = nullCipher{}
 	}
 	hc.trafficSecret = secret
-	if hc.isDTLS && protocolVersion == VersionTLS13 {
+	if hc.isDTLS {
+		// TODO(crbug.com/42290594): This will need to handle KeyUpdate.
 		hc.setEpoch(uint16(level))
 	} else {
 		hc.incEpoch()