Disable height.modifies_zoom (#564)

# Description

Height Sliders modifying zoom was always going to be temporary, and long
term we had planned on phasing it out in favor of allowing Physics to be
the balancing factor against players making their characters small. Now
that we have features such as Space Wind, Mass Contests, Frictionless
Space, and so on, this has come to fruition, and we no longer
necessarily need zoom-adjusting to be a balancing factor. Zoom is cited
as one of the most common complaints about our codebase, players
absolutely seem to not like this, especially since it's not communicated
to them in character creation that their viewmodel is going to be
adjusted.

This PR does not permanently remove the Modifies_Zoom feature, merely
setting it to false by default. Server hosts are still able to re-enable
it in their TOML configs if desired, but by default it should be
disabled.

Content.Shared/CCVar/CCVars.cs

@@ -2272,7 +2272,7 @@ public static readonly CVarDef<float>
         ///     Whether height & width sliders adjust a player's max view distance
         /// </summary>
         public static readonly CVarDef<bool> HeightAdjustModifiesZoom =
-            CVarDef.Create("heightadjust.modifies_zoom", true, CVar.SERVERONLY);
+            CVarDef.Create("heightadjust.modifies_zoom", false, CVar.SERVERONLY);
 
         /// <summary>
         ///     Enables station goals