Fix 'maxValue' not working for strength

`maxDiff` was initialized at `0`, which led to problems when the
difference in attribute ratio was nominally negative.

There is secondary issue that needs to be fixed related to this, but
at least this ensures that maximum value always applies as a limit.

The other issue is that target ratios should be recalculated if a
maximum value is reached because it changes the relative weights of the
remaining attributes. Will be done in separate commit

Author: majochem

src/Classes/PassiveSpec.lua

@@ -2210,7 +2210,7 @@ function PassiveSpecClass:GetAutoAttribute(cachedPlayerAttr, cachedPathAttrResul
 	playerAttr.int.ratio = playerAttr.int.total / playerAttr.sumTotal
 	playerAttr.str.ratio = playerAttr.str.total / playerAttr.sumTotal
 
-	local maxDiff = 0
+	local maxDiff = nil
 	local neededAttr = nil
 
 	-- Update weights based on attribute requirements if necessary
@@ -2222,7 +2222,7 @@ function PassiveSpecClass:GetAutoAttribute(cachedPlayerAttr, cachedPathAttrResul
 		-- Check if the max value is set and if it's already been exceeded.
 		if autoAttributeConfig[attr].max == nil or (not autoAttributeConfig[attr].useMaxVal) or playerAttr[attr].total < autoAttributeConfig[attr].max then
 			local diff = autoAttributeConfig[attr].ratio - playerAttr[attr].ratio
-			if diff > maxDiff then
+			if (maxDiff == nil) or (diff > maxDiff) then
 				maxDiff = diff
 				neededAttr = attr
 			end