Added tasks option to execution rerun

[be-kate]

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]

All committers have signed the CLA.

[jpavlav]

@cognifloyd 👋 Not 100% sure if you're the right person to ping, but it would be super handy to get someone from from the tsc to review this.