Update example value for min-gas price when using mainnet config

[iramiller]

Summary

When a user is running the provenanced command in mainnet mode the minimum gas price must be greater than one... unfortunately the example value is a small fraction (as expected for testnet configuration that attempt to minimize gas use).

Resolution

Update the example value to be appropriate for both mainnet/testnet configuration.

provenance/cmd/provenanced/cmd/root.go

Line 259 in 142380e

panic(fmt.Errorf("invalid min-gas-price value, expected single decimal coin value such as '0.0025%s', got '%s';\n\n %w",