Return proper responses for SCIM provisioned identities

[tenyo]

This PR adds return responses to ListSCIMProvisionedIdentities and GetSCIMProvisioningInfoForUser, as before it was not possible to get the output of those calls.
Fixes #2338

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[codecov]

Codecov Report

Merging #2474 (ce48d9d) into master (8a4bdb5) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2474   +/-   ##
=======================================
  Coverage   98.03%   98.03%           
=======================================
  Files         122      122           
  Lines       10695    10705   +10     
=======================================
+ Hits        10485    10495   +10     
  Misses        144      144           
  Partials       66       66           

Impacted Files	Coverage Δ
github/scim.go	100.00% <100.00%> (ø)

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[gmlewis]

Thank you, @tenyo !
Just a couple minor nits, please, and then we should be ready for a second LGTM+Approval from any other contributor to this repo.

[gmlewis]

Thank you, @tenyo !
LGTM.

Awaiting second LGTM+Approval from any other contributor to this repo before merging.

[gmlewis]

Thank you, @wesleimp !
Merging.