DatabaseRewinder should not delete internal metadata table

[akihiro17]

This commit fixes the following error in Rails 5.0.

$ bundle exec rspec spec # DatabaseRewinder deletes the internal metadata table
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DELETE FROM `ar_internal_metadata`;
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$ RAILS_ENV=test bundle exec rake db:migrate reset
rake aborted!
ActiveRecord::NoEnvironmentInSchemaError:

Environment data not found in the schema. To resolve this issue, run:

        bin/rails db:environment:set RAILS_ENV=test

Tasks: TOP => db:migrate:reset => db:drop => db:check_protected_environments
(See full trace by running task with --trace)

[amatsuda]

@akihiro17 Thank you!!

[amatsuda]

Just released version 0.6.2 gem including this fix.

[akihiro17]

@amatsuda Thank you