Address Layout/IndentationWidth cop offenses

This commit addresses RuboCop offenses reported at
https://buildkite.com/rails/rails/builds/107320#018f8835-b770-4068-9b97-0aec28c7ddb3

- Offenses are addressed by RuboCop auto correction as follows
```
$ bundle exec rubocop -a activerecord/test/cases/connection_adapters/type_lookup_test.rb
Inspecting 1 file
C

Offenses:

activerecord/test/cases/connection_adapters/type_lookup_test.rb:91:9: C: [Corrected] Layout/IndentationWidth: Use 2 (not 3) spaces for indentation.
           %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0) number(2) number(2,0)}.each do |type|
        ^^^
activerecord/test/cases/connection_adapters/type_lookup_test.rb:92:11: C: [Corrected] Layout/IndentationWidth: Use 2 (not 3) spaces for indentation.
             cast_type = @connection.send(:type_map).lookup(type)
          ^^^
activerecord/test/cases/connection_adapters/type_lookup_test.rb:94:14: C: [Corrected] Layout/IndentationConsistency: Inconsistent indentation detected.
             assert_equal :decimal, cast_type.type
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
activerecord/test/cases/connection_adapters/type_lookup_test.rb:95:14: C: [Corrected] Layout/IndentationConsistency: Inconsistent indentation detected.
             assert_equal 2, cast_type.cast(2.1)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

1 file inspected, 4 offenses detected, 4 offenses corrected
$
```

Follow up rails#51826

Author: yahonda

activerecord/test/cases/connection_adapters/type_lookup_test.rb

@@ -88,12 +88,12 @@ def test_bigint_limit
         end
 
         def test_decimal_without_scale
-           %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0) number(2) number(2,0)}.each do |type|
-              cast_type = @connection.send(:type_map).lookup(type)
+          %w{decimal(2) decimal(2,0) numeric(2) numeric(2,0) number(2) number(2,0)}.each do |type|
+            cast_type = @connection.send(:type_map).lookup(type)
 
-              assert_equal :decimal, cast_type.type
-              assert_equal 2, cast_type.cast(2.1)
-           end
+            assert_equal :decimal, cast_type.type
+            assert_equal 2, cast_type.cast(2.1)
+          end
         end
 
         private