Add the pattern_type property to the configuration entity

To implement new features the configuration entity should have a pattern_type property, which for now just replaces the access_type property, but in future will have other purposes too.

The plan is:

• Define a new pattern_type property for the configuration entity
• Change the configuration entity to export the pattern_type property instead of the access_type property
• Implement hook_update_N() to populate the new property from the existing access_type property
• Change the code to use the new property
• Mark the access_type property deprecated

For the last step is also necessary to create a change record, since the deprecation message must contain a link to a change record.