Add AssertSoft String overload for Java Api (#5475)

This adds a String overload for AssertSoft.
Previously only integer weights could have been used,
limiting the user. With Strings the user can now use
e.g. Java's BigInteger class converted to a String instead.

src/api/java/Optimize.java

@@ -173,10 +173,21 @@ public String toString()
      *
      **/
     public Handle<?> AssertSoft(Expr<BoolSort> constraint, int weight, String group)
+    {
+        return AssertSoft(constraint, Integer.toString(weight), group);
+    }
+
+    /**
+     * Assert soft constraint
+     *
+     * Return an objective which associates with the group of constraints.
+     *
+     **/
+    public Handle<?> AssertSoft(Expr<BoolSort> constraint, String weight, String group)
     {
         getContext().checkContextMatch(constraint);
         Symbol s = getContext().mkSymbol(group);
-        return new Handle<>(this, Native.optimizeAssertSoft(getContext().nCtx(), getNativeObject(), constraint.getNativeObject(), Integer.toString(weight), s.getNativeObject()));
+        return new Handle<>(this, Native.optimizeAssertSoft(getContext().nCtx(), getNativeObject(), constraint.getNativeObject(), weight, s.getNativeObject()));
     }
 
     /**