Set the fabric index correctly

[todo]

connectedhomeip/src/protocols/secure_channel/CASESession.cpp

Lines 163 to 169 in 7304eaa

	// TODO: Set the fabric index correctly
	mLocalFabricIndex = cachableSession.mLocalFabricIndex;
	memcpy(mResumptionId, cachableSession.mResumptionId, sizeof(mResumptionId));
	const ByteSpan * ipkListSpan = GetIPKList();
	VerifyOrReturnError(ipkListSpan->size() == sizeof(mIPK), CHIP_ERROR_INVALID_ARGUMENT);

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This issue was generated by todo based on a TODO comment in 7304eaa when #11937 was merged. cc @nivi-apple.