v4.2.1

GraphPPL v4.2.1

Diff since v4.2.0

Merged pull requests:

• CompatHelper: bump compat for GraphPlot in [weakdeps] to 0.6, (keep existing compat) (#236) (@github-actions[bot])
• Constants increase model counter twice (#238) (@wouterwln)
• Remove gensym function for model (#239) (@wouterwln)