Changes to Demographics API

the query request parameter year was restricted to a list of enum values

added the pattern ^\d{4}$ to the path request parameter postcode

the demographics/items/items/items/value response's property format changed from int32 to no format for status 200

the demographics/items/total response's property format changed from int64 to no format for status 200

the demographics/items/year response's property format changed from int32 to no format for status 200

added the new enum value 2011.00 to the query request parameter year

added the new enum value 2016.00 to the query request parameter year

added the new enum value 2021.00 to the query request parameter year

for the query request parameter year, the format was generalized from int32 to no format

added the non-success response with the status 400

added the non-success response with the status 401

added the non-success response with the status 500

the path request parameter postcode became required