[TC-OO-2.6] YAML script needs to be added for newly added test case(TC-OO-2.6).

[Ashwinigrl]

Description:

• TC-OO-2.6 Has been newly added to the On/Off cluster Test plan. So Yaml script has to be added for this newly added test case.

Test Plan References:

• https://github.com/CHIP-Specifications/chip-test-plans/blob/master/src/cluster/onoff.adoc#416-tc-oo-26--offonly-feature-with--dut_server

Yaml Script References:

• https://github.com/project-chip/connectedhomeip/tree/master/src/app/tests/suites/certification