Special f64 values in histograms are not printed using the Go library conventions

Special `f64` values in histograms are currently not printed using the Go library conventions, i.e., instead of "+Inf", "-Inf", "NaN", the values are printed out using the rust library conventions "inf", "-inf", and "nan", respectively. For values other than ones in histograms, the values are correctly wrapped using the `FormattedValue` struct.