ggplot v3.4.0 will create linewidth param, and distinguish this from size

[davidhodge931]

For {ggblanket} 1.2.0, just remove size arg, so that size/linewidth can be accessed by ... without causing problems

For future {ggblanket} version once {ggplot2} 3.4.0 released:

• Add linewidth param with default 1.5
• Add size param with default 0.5