Fix formatting and suppress deprecation warnings

- Formatted all files with dart format
- Added deprecated_member_use_from_same_package: ignore to analysis_options.yaml
- This suppresses warnings for using deprecated classes within the package during deprecation period

Author: escamoteur

analysis_options.yaml

@@ -7,6 +7,8 @@ analyzer:
     - example/**
     - example_command_results/**
     - counter_example/**
+  errors:
+    deprecated_member_use_from_same_package: ignore
 
 linter:
   rules:

example/lib/verify_fixes.dart

@@ -2,7 +2,7 @@ import 'package:command_it/command_it.dart';
 
 class Test {
   final cmd = Command.createAsyncNoParamNoResult(() async {});
-  
+
   void test() {
     cmd.execute();
     cmd.executeWithFuture();