Remove gas price from 0x and 1Inch requests

[MartinquaXD]

To not exceed any request limits for expensive DEX APIs there is an nginx egress proxy that caches requests to not waste RPS on identical requests.
This for example enables multiple API pods to only issue 1 actual request to the DEX API while receiving the response for all of them.
However, this currently only works if the requested URL is actually completely identical. So far the gas price got specified with the request which means whenever the gas price changes slightly caching will not be possible.
In order to switch to the dex solver being used as quoters in a colocated manner this has to be addressed.
Luckily 0x and 1Inch use reasonable default values for the gas price so we don't actually have to provide them and there is no nginx caching for balancer so we don't have to worry about that either.

Removes gasPrice from the requests and updates unit tests accordingly.

[fleupold]

I'm surpised this is an issue. I was under the assumption the gas price only changes when the block number changes and DEX requests are already cached only for the current block?

[MartinquaXD]

Yeah, I think you are right. I did a test run on prod and didn't see any crazy spikes in rate limits and such. 👌