Tests

Upgrade govuk-frontend supported version to 5.6.0 (#557) #1383

Job	Run time
Code quality, test coverage and documentation checks	1m 59s
Testing with Ruby 3.1.6 and Rails 6.1.7	1m 24s
Testing with Ruby 3.1.6 and Rails 7.0.8	1m 25s
Testing with Ruby 3.1.6 and Rails 7.1.3	1m 27s
Testing with Ruby 3.2.4 and Rails 6.1.7	1m 29s
Testing with Ruby 3.2.4 and Rails 7.0.8	1m 25s
Testing with Ruby 3.2.4 and Rails 7.1.3	1m 24s
Testing with Ruby 3.3.4 and Rails 6.1.7	1m 25s
Testing with Ruby 3.3.4 and Rails 7.0.8	1m 26s
Testing with Ruby 3.3.4 and Rails 7.1.3	1m 29s
Permit merge	1s
	14m 54s

Provide feedback