Update macos-integration-tests.yml

Author: FeodorFitsner

.github/workflows/macos-integration-tests.yml

@@ -7,7 +7,7 @@ on:
 env:
   FLUTTER_VERSION: "3.32.8"
   FLET_TEST_SCREENSHOTS_PIXEL_RATIO: "2.0"
-  FLET_TEST_SIMILARITY_THRESHOLD: "99.0"
+  FLET_TEST_SCREENSHOTS_SIMILARITY_THRESHOLD: "99.0"
   FLET_TEST_DISABLE_FVM: "1"
 
 jobs: