chore(analysis): exclude example directories from analyzer

Adds analyzer exclusions for example/ and example_with_tests/ directories to prevent analyzing example code

Author: Nikoro

analysis_options.yaml

@@ -1,5 +1,10 @@
 include: package:flutter_lints/flutter.yaml
 
+analyzer:
+  exclude:
+    - example/**
+    - example_with_tests/**
+
 linter:
   rules:
     avoid_function_literals_in_foreach_calls: false