Added task option to execution rerun

[be-kate-do]

Description

In order to be able to re-run the execution from specific task, this parameter needs to be exposed in execution re-run method.

Execution is capable to handle this parameter according to this : https://github.com/StackStorm/st2/blob/master/st2client/st2client/commands/action.py#L1790-L1793

Testing:

Tested locally, rerunning the workflow by id and supplying the task parameter.
Relevant output from the re_run:

    "context": {
      "re-run": {
        "ref": "682f7b112a47c69a4be47e02",
        "tasks": [
          "check_if_empty"
        ],
        "reset": [
          "check_if_empty"
        ]
      },

[CLAassistant]

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