fix: helix requires uppercase, and doesn't provide volume

[PFC-developer]

fix helix as a provider.

it retrieves price quotes, but volume is not available via the API call. (so I returned it as one).

pushing it up to see if people have better options for volume

[PFC-developer]

to test
add

[[currency_pairs]]
base="WUSDM"
quote="USDT"
providers = ["helix"]

[[currency_pairs]]
base="MOTHER"
quote="INJ"
providers = ["helix"]

[[currency_pairs]]
base="GME"
quote="INJ"
providers = ["helix"]

[[currency_pairs]]
base="PYUSD"
quote="USDT"
providers = ["helix"]

[[currency_pairs]]
base="USDY"
quote="USDT"
providers = ["helix"]

[[provider_endpoints]]
name = "helix"
url_set = "api_injective"

[helix]
token_file = "https://raw.githubusercontent.com/InjectiveLabs/injective-lists/master/tokens/mainnet.json"

[url_set.api_injective]
urls = [
  "your favorite API"
]

[PFC-developer]

code doesn't take into account different decimals. present in some markets. do not apply

[PFC-developer]

code now uses a external file (settable in config) to get the list of tokens, and their decimal size.
it skips tokens where price spread if > 10% (helix only)

[PFC-developer]

@starsquidnodes any chance for a review/merge?