Fix Flexbox offset

Was off by one, leading to the outer pixel getting cut off at the boundary

Basalt/objects/Flexbox.lua

@@ -25,11 +25,11 @@ return function(name, basalt)
     
         local availableSpace = (flexDirection == "row" and width or height) - totalChildSize - (spacing * (totalElements - 1))
     
-        local currentOffset = 0
+        local currentOffset = 1
         if justifyContent == "center" then
-            currentOffset = availableSpace / 2
+            currentOffset = 1 + availableSpace / 2
         elseif justifyContent == "flex-end" then
-            currentOffset = availableSpace
+            currentOffset = 1 + availableSpace
         end
     
         for _, obj in ipairs(objects) do
@@ -92,4 +92,4 @@ return function(name, basalt)
 
     object.__index = object
     return setmetatable(object, base)
-end
+end