Update Chrome and Firefox versions.

Chrome version: 143.0.7499.4
Firefox version: 144.0.2

Change-Id: I6c8f098777dd8e7d89d9548d0cc81ea8e3f4c2c5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/459880
Commit-Queue: Nate Biggs <natebiggs@google.com>
Reviewed-by: Mark Zhou <markzipan@google.com>

Author: natebiggs

DEPS

@@ -163,9 +163,9 @@ vars = {
   # meant to be downloaded by users for local testing. You can self-service
   # update these by following the go/dart-engprod/browsers.md instructions.
   "download_chrome": False,
-  "chrome_tag": "142.0.7444.34",
+  "chrome_tag": "143.0.7499.4",
   "download_firefox": False,
-  "firefox_tag": "144.0",
+  "firefox_tag": "144.0.2",
 
   # Emscripten is used in dart2wasm tests.
   "download_emscripten": False,