Add test cases for JSON resource marshaling - SCIM

[elminster-aom]

Resources Covered:

• SCIMProvisionedGroups

Related Issue: #55

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.17%. Comparing base (53d0e6a) to head (652c97c).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@ Coverage Diff @@## master #3798 +/- ##
=======================================
Coverage 92.17% 92.17% =======================================
Files 191 191 Lines 13690 13690 =======================================
Hits 12619 12619 Misses 883 883 Partials 188 188 

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[gmlewis]

Thank you, @elminster-aom!
LGTM.
Merging.