use `simulate_operation` instead of `run_operation`

[nicolasochem]

run_operation is deprecated and simulate_operation might give better estimates in order to calculate gas fees and avoid issues such as the one we had during N migraiton.

[yurug]

The documentation is here: https://gitlab.com/-/sandbox/swagger#/default/post_helpers_scripts_simulate_operation

It will be improved but here is some curated description of the parameters:

• successor_level : if true, the simulation is done on the successor level of the current context, not the current context. That's a very technical parameter that should be ignored by the mere mortals. Mainly used in tests.

• latency: an integer that estimates how many blocks to wait before inclusion.

• blocks_before_activation: If we are close to a protocol activation, this parameter should be set. Indeed, at activation time, the cache is cleared, so the estimation is impacted. This parameter can be safely ignored.