format tuple params as json arrays in SafeTxBuilder

[jalbrekt85]

this allows us to pass in simple tuple params instead of having to json serialize the param when interfacing with safetxbuilder

so we can do this:

campaign_params = (chain_id, gauge_address, ...,)
campaign_manager.createCampaign(campaign_params, ...)

instead of this

campaign_params = json.dumps([str(chain_id), gauge_address, ...,], separators=(',', ':'))
campaign_manager.createCampaign(campaign_params, ...)

[gosuto-inzasheru]

lgtm!