Add specs for redundant SafeAutoCorrect: true and AutoCorrect: true

This PR adds specs redandant `SafeAutoCorrect: true` and `AutoCorrect: true` config:
And it removes the redundant config detected below to fix the failed specs:

```console
$ bundle exec rspec spec/project_spec.rb
(snip)

Failures:

  1) RuboCop Project default configuration file does not include `AutoCorrect: true`
     Failure/Error: expect(safe).not_to be(true), "`#{name}` has unnecessary `#{metadata}: true` config."
       `Layout/LineContinuationSpacing` has unnecessary `AutoCorrect: true` config.
     # ./spec/project_spec.rb:131:in `block (5 levels) in <top (required)>'
     # ./spec/project_spec.rb:129:in `each'
     # ./spec/project_spec.rb:129:in `block (4 levels) in <top (required)>'

  2) RuboCop Project default configuration file does not include `SafeAutoCorrect: true`
     Failure/Error: expect(safe).not_to be(true), "`#{name}` has unnecessary `#{metadata}: true` config."
       `Layout/LineContinuationSpacing` has unnecessary `SafeAutoCorrect: true` config.
     # ./spec/project_spec.rb:131:in `block (5 levels) in <top (required)>'
     # ./spec/project_spec.rb:129:in `each'
     # ./spec/project_spec.rb:129:in `block (4 levels) in <top (required)>'

Finished in 2.12 seconds (files took 1.12 seconds to load)
107 examples, 2 failures

Failed examples:

rspec './spec/project_spec.rb[1:1:12]' # RuboCop Project default configuration file does not include `AutoCorrect: true`
rspec './spec/project_spec.rb[1:1:11]' # RuboCop Project default configuration file does not include `SafeAutoCorrect: true`
```

config/default.yml

@@ -1016,8 +1016,6 @@ Layout/LineContinuationLeadingSpace:
 Layout/LineContinuationSpacing:
   Description: 'Checks the spacing in front of backslash in line continuations.'
   Enabled: pending
-  AutoCorrect: true
-  SafeAutoCorrect: true
   VersionAdded: '1.31'
   EnforcedStyle: space
   SupportedStyles:

spec/project_spec.rb

@@ -124,10 +124,12 @@ def expected
     end
     # rubocop:enable RSpec/NoExpectationExample
 
-    it 'does not include `Safe: true`' do
-      cop_names.each do |name|
-        safe = config.dig(name, 'Safe')
-        expect(safe).not_to be(true), "`#{name}` has unnecessary `Safe: true` config."
+    %w[Safe SafeAutoCorrect AutoCorrect].each do |metadata|
+      it "does not include `#{metadata}: true`" do
+        cop_names.each do |cop_name|
+          safe = config.dig(cop_name, metadata)
+          expect(safe).not_to be(true), "`#{cop_name}` has unnecessary `#{metadata}: true` config."
+        end
       end
     end
   end