Adding plan modifier for manager reset

[prajwalpatil25]

As manager reset doesn't need to perform any update operation because every time user wants to reset manager, it should perform reset action. So, added plan modifiers for id and reset type attributes and removed implementation for update(which was doing same thing as create).

=== RUN   TestAccRedfishManagerReset_Invalid_ResetType_Negative
--- PASS: TestAccRedfishManagerReset_Invalid_ResetType_Negative (0.20s)
=== RUN   TestAccRedfishManagerReset_Invalid_ManagerID_Negative
--- PASS: TestAccRedfishManagerReset_Invalid_ManagerID_Negative (7.28s)
=== RUN   TestAccRedfishManagerReset_Update_Negative
--- PASS: TestAccRedfishManagerReset_Update_Negative (225.17s)
=== RUN   TestAccRedfishManagerReset_Create
--- PASS: TestAccRedfishManagerReset_Create (221.86s)
PASS