Fix example/all.yaml ordering to make Travis happy (#2210)

diff --git a/example/all.yaml b/example/all.yaml
index d68d3bf..aa9cd42 100644
--- a/example/all.yaml
+++ b/example/all.yaml
@@ -151,9 +151,9 @@
     - unnecessary_getters_setters
     - unnecessary_lambdas
     - unnecessary_new
-    - unnecessary_nullable_for_final_variable_declarations
     - unnecessary_null_aware_assignments
     - unnecessary_null_in_if_null_operators
+    - unnecessary_nullable_for_final_variable_declarations
     - unnecessary_overrides
     - unnecessary_parenthesis
     - unnecessary_raw_strings