Fix: Warning: `qplot()` was deprecated in ggplot2 3.4.0.

[gregorgorjanc]

data(AlphaPart.ped)
part <- AlphaPart(x = AlphaPart.ped,
                  colPath = "country",
                  colBV = "bv1")
sumPartByGen <- summary(part, by = "gen")
plot(sumPartByGen)
## Warning: `qplot()` was deprecated in ggplot2 3.4.0.
## ℹ The deprecated feature was likely used in the AlphaPart package.
##   Please report the issue to the authors.
## This warning is displayed once every 8 hours.
## Call `lifecycle::last_lifecycle_warnings()` to see where this warning was
## generated.