Add tooltip for logistic group caption

Helps when the name is too long and gets truncated.

src/scripts/gui.lua

@@ -328,6 +328,7 @@ local function update_cs_signals(state)
     state.cs_signals_group_checkbox.state = section.active
     local caption = create_logistic_section_caption(section)
     state.cs_signals_group_checkbox.caption = caption
+    state.cs_signals_group_checkbox.tooltip = caption
   end
   for name, data in pairs(config.cs_signals) do
     local value = state.combinator:get_cs_value(name)
@@ -2121,6 +2122,7 @@ local function create_window(player, combinator)
               type = "checkbox",
               name = "cs_signals_group_checkbox",
               caption = cs_caption,
+              tooltip = cs_caption,
               style = "caption_checkbox",
               style_mods = {
                 horizontally_squashable = true