Upgrade grpc to v1.78.1

Yash Chauhan · Yash Chauhan · commit 3f8ec86ae04b · 2026-03-10T20:21:50.000+05:30
diff --git a/third_party/grpc b/third_party/grpc
@@ -1 +1 @@
-Subproject commit 5e6ba94242b92e363220bc2163d55ce3554d4ecc
+Subproject commit 5b6492ea90b2b867a6adad1b10a6edda28e860d1
