CPS-401 Update Open API YAML with data types and example for output (cpsData)

CPS-401 Update Open API YAML with data types and example for output (cpsData)

-added response for get data nodes based on dataspace and anchor
-modified modelmapper jn DataRestControllerSpec to be Spy not Mock
-when openapi.yaml is entered into https://editor.swagger.io/ it
displays however locally it does not, This may be due to file
segmentation but this is still unclear.
-moved files from docs/openapi to src/main/resources/static as required
for new swagger sprindoc

Issue-ID: CPS-401

Change-Id: I45286530d9a9ca85b56c0a656a44675398a003f4
Signed-off-by: JosephKeenan <joseph.keenan@est.tech>