Tweak offense highlight range for `Style/RedundantFileExtensionInRequ…

…ire`

This PR tweaks offense highlight range for `Style/RedundantFileExtensionInRequire`.

## Before

```console
require 'foo.rb'
        ^^^^^^^^ Redundant `.rb` file extension detected.
```

## After

```console
require 'foo.rb'
            ^^^ Redundant `.rb` file extension detected.
```

lib/rubocop/cop/style/redundant_file_extension_in_require.rb

@@ -25,6 +25,7 @@ module Style
       #   require_relative '../foo.so'
       #
       class RedundantFileExtensionInRequire < Base
+        include RangeHelp
         extend AutoCorrector
 
         MSG = 'Redundant `.rb` file extension detected.'
@@ -39,13 +40,21 @@ def on_send(node)
           require_call?(node) do |name_node|
             return unless name_node.value.end_with?('.rb')
 
-            add_offense(name_node) do |corrector|
-              correction = name_node.value.delete_suffix('.rb')
+            extension_range = extension_range(name_node)
 
-              corrector.replace(name_node, "'#{correction}'")
+            add_offense(extension_range) do |corrector|
+              corrector.remove(extension_range)
             end
           end
         end
+
+        private
+
+        def extension_range(name_node)
+          end_of_path_string = name_node.source_range.end_pos
+
+          range_between(end_of_path_string - 4, end_of_path_string - 1)
+        end
       end
     end
   end

spec/rubocop/cop/style/redundant_file_extension_in_require_spec.rb

@@ -4,9 +4,9 @@
   it 'registers an offense and corrects when requiring filename ending with `.rb`' do
     expect_offense(<<~RUBY)
       require 'foo.rb'
-              ^^^^^^^^ Redundant `.rb` file extension detected.
+                  ^^^ Redundant `.rb` file extension detected.
       require_relative '../foo.rb'
-                       ^^^^^^^^^^^ Redundant `.rb` file extension detected.
+                              ^^^ Redundant `.rb` file extension detected.
     RUBY
 
     expect_correction(<<~RUBY)