Implement TC-OPCREDS-3.2

[tcarmelveilleux]

Problem

TC-OPCREDS-3.2 (https://github.com/CHIP-Specifications/chip-test-plans/blob/master/src/devicemanagement.adoc#tc-opcreds-3-2-attribute-currentfabricindex-validation-dut-server) is very complex test that requires particular procedures not realizable by hand with chip-tool, especially regarding complex cryptographic values.

Proposed Solution

Implement TC-OPCREDS-3.2 with matter_testing_support Python module and associated API updates if needed.