Dart 3.7: dart format no longer supports --fix

Just drop it, the most important is that code is formatted.

Author: greenrobot-team

.github/workflows/code-analysis.yml

@@ -45,7 +45,7 @@ jobs:
           dart analyze objectbox
           dart analyze objectbox_test
       - name: Check formatting of all packages
-        run: dart format --set-exit-if-changed --fix .
+        run: dart format --set-exit-if-changed .
 
   pana:
     runs-on: ubuntu-24.04

.gitlab-ci.yml

@@ -57,7 +57,7 @@ analyze-and-format:
     - dart analyze objectbox_test
     - dart analyze objectbox/example/dart-native/vectorsearch_cities
     # Check formatting of all packages
-    - dart format --set-exit-if-changed --fix .
+    - dart format --set-exit-if-changed .
 
 # Runs generator integration tests, e.g. ensures generator works as expected.
 # Note: no need to test oldest SDK here, generator package is also built as part of unit-tests job.