SignEdit for Bukkit

Fixed

• java.lang.IllegalStateException: Unable to call method: getSide on Bukkit 1.19.4 due to incomplete sign side support in that version of Bukkit

Under the Hood

• SignHelpers.setEditableOldApi() called the wrong Bukkit method (should be Sign.setEditable() instead of Sign.setWaxed()), but this probably has no practical effect. It only affects the correctness of how this plugin interacts with Bukkit 1.13.2 through Bukkit 1.19.4.
• The sign side calculation based on the player's relative position from the sign (SideShim.fromRelativePosition) will now say front on Bukkit 1.19.4 and older, as the back side had not yet been added in those versions of Bukkit.