Fix issue where .rubocop_todo.yml is poorly formatted (#29)

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    package_protections (2.2.0)
+    package_protections (2.2.1)
       activesupport
       parse_packwerk
       rubocop

lib/package_protections/private.rb

@@ -153,6 +153,8 @@ def self.exclude_for_rule(rule)
       excludes = T.let(Set.new, T::Set[String])
 
       Private.rubocop_todo_ymls.each do |todo_yml|
+        next if !todo_yml
+
         config = todo_yml[rule]
         next if config.nil?
 

package_protections.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |spec|
   spec.name          = 'package_protections'
-  spec.version       = '2.2.0'
+  spec.version       = '2.2.1'
   spec.authors       = ['Gusto Engineers']
   spec.email         = ['[email protected]']
   spec.summary       = 'Package protections for Rails apps'

spec/package_protections_spec.rb

@@ -808,6 +808,17 @@ def get_new_violations
             )
           end
 
+          it 'does not fail if a .rubocop_todo.yml is in the wrong format' do
+            apples_package_yml_with_namespace_protection_set_to_fail_on_any
+
+            write_file('packs/apples/app/public/tool.rb', '')
+            write_file('packs/apples/.rubocop_todo.yml', <<~YML.strip)
+            YML
+
+            offenses = PackageProtections.get_offenses(packages: get_packages, new_violations: [])
+            expect(offenses).to contain_exactly(0).offense
+          end
+
           it 'succeeds if another pack\'s file is in the rubocop TODO' do
             apples_package_yml_with_namespace_protection_set_to_fail_on_any