Update WebRTC code version (2022-09-29T04:07:18).

Bug: None
Change-Id: Ib8ad9e36a6bb3861b38b1917626e1166394cb990
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/277361
Commit-Queue: webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com <webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com>
Bot-Commit: webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com <webrtc-version-updater@webrtc-ci.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#38239}

call/version.cc

diff --git a/call/version.cc b/call/version.cc
index 5ded115..77d5a91 100644
--- a/call/version.cc
+++ b/call/version.cc
@@ -13,7 +13,7 @@
 namespace webrtc {
 
 // The timestamp is always in UTC.
-const char* const kSourceTimestamp = "WebRTC source stamp 2022-09-28T04:12:23";
+const char* const kSourceTimestamp = "WebRTC source stamp 2022-09-29T04:07:18";
 
 void LoadWebRTCVersionInRegister() {
   // Using volatile to instruct the compiler to not optimize `p` away even