[flutter_releases] Roll engine to 56b99a6 (#102401)

* [flutter_releases] Roll engine to 56b99a6

* empty commit

* empty commit
diff --git a/bin/internal/engine.version b/bin/internal/engine.version
index 8d4497d..4ae1eb6 100644
--- a/bin/internal/engine.version
+++ b/bin/internal/engine.version
@@ -1 +1 @@
-6e9953c743365c676289e605dda4e1ddcdf07f24
+56b99a67af56611d81ae6fcbf2bc471103157e06