[Docs][SCIM2][IS 5.6.0] add "/scim2/Bulk" to Swagger documentation

[hauntingEcho]

The endpoint "/scim2/Bulk", mentioned in the IS scim2 endpoint list and in RFC 7644 section 3.7, is missing from the Swagger SCIM2 documentation

[ruwanta]

Although Bulk operation can be supported on the SCIM (REST) Level, it is highly unlikely all underlying user stores can support it.
Especially it will take few seconds to minutes to complete large bulk operation having different operators.
Hence we better not implement bulk operation without re-architecting the underlying user-core and user-store contracts/capabilities.