Adjust variance factor calculation for contract force rolls

Updated the variance factor values in the contract force calculation to improve balance and align with gameplay goals. This change modifies the outcomes for specific roll values, making the distribution more gradual and consistent.

MekHQ/src/mekhq/campaign/market/contractMarket/AbstractContractMarket.java

@@ -213,12 +213,12 @@ public int calculateRequiredLances(Campaign campaign, AtBContract contract, bool
         // Otherwise, we roll to determine the amount we divide availableForces by
         int roll = d6(2);
         double varianceFactor = switch (roll) {
-            case 2 -> 6;
-            case 3 -> 5;
-            case 4 -> 4;
-            case 10 -> 2;
-            case 11 -> 1;
-            case 12 -> 0;
+            case 2 -> 4.5;
+            case 3 -> 4;
+            case 4 -> 3.5;
+            case 10 -> 2.5;
+            case 11 -> 2;
+            case 12 -> 1.5;
             default -> 3;
         };