feat(price-feeder): add mexc provider

[adamewozniak]

Adds the mexc provider 🚀

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[robert-zaremba]

I would prefer if we focus with all team towards beta release.

• QA are not done, and we need to do more crash tests of the oracle.
• we can always add new provider once we have chain RC.
• we also need support with liveness tests.

So if not a problem - can we push back finalization of this task for later, until we have RC?

[RafilxTenfen]

I saw that this provider has Umee prices, but when I tried to put it in the config to get prices "UMEEUSDT" but I keep receiving

10:09PM INF skipping until next voting period current_vote_period=5 module=oracle previous_vote_period=5 vote_period=5
10:09PM ERR failed to get ticker prices from provider error="mexc failed to get candle price for UMEE_USDT" module=oracle

This is because no one traded umee?

[RafilxTenfen]

LGTM

Only question about umee prices in mexc provider

[adamewozniak]

I saw that this provider has Umee prices, but when I tried to put it in the config to get prices "UMEEUSDT" but I keep receiving

10:09PM INF skipping until next voting period current_vote_period=5 module=oracle previous_vote_period=5 vote_period=5

10:09PM ERR failed to get ticker prices from provider error="mexc failed to get candle price for UMEE_USDT" module=oracle

This is because no one traded umee?

Yeah, this'll happen if there's 0 volume for a given pair over the last 3 minutes. Did you test with another pair @RafilxTenfen ?

[RafilxTenfen]

I saw that this provider has Umee prices, but when I tried to put it in the config to get prices "UMEEUSDT" but I keep receiving

10:09PM INF skipping until next voting period current_vote_period=5 module=oracle previous_vote_period=5 vote_period=5

10:09PM ERR failed to get ticker prices from provider error="mexc failed to get candle price for UMEE_USDT" module=oracle

This is because no one traded umee?

Yeah, this'll happen if there's 0 volume for a given pair over the last 3 minutes. Did you test with another pair @RafilxTenfen ?

Yes, ATOMUSDT worked