Math.Truncate rounds towards 0. Use FIX instead of INT to match that behaviour (CirrusRedOrg#282)

Author: ChrisJollyAU

src/EFCore.Jet/Query/ExpressionTranslators/Internal/JetMathTranslator.cs

@@ -226,7 +226,7 @@ public class JetMathTranslator(ISqlExpressionFactory sqlExpressionFactory) : IMe
                     resultType = typeof(double);
                 }
                 var result = (SqlExpression)_sqlExpressionFactory.Function(
-                    "INT",
+                    "FIX",
                     [argument],
                     nullable: true,
                     argumentsPropagateNullability: [true],

test/EFCore.Jet.FunctionalTests/Query/NorthwindFunctionsQueryJetTest.Functions.cs

@@ -81,7 +81,7 @@ public override async Task Sum_over_truncate_works_correctly_in_projection(bool
             AssertSql(
                 """
 SELECT `o`.`OrderID`, (
-    SELECT IIF(SUM(INT(`o0`.`UnitPrice`)) IS NULL, 0.0, SUM(INT(`o0`.`UnitPrice`)))
+    SELECT IIF(SUM(FIX(`o0`.`UnitPrice`)) IS NULL, 0.0, SUM(FIX(`o0`.`UnitPrice`)))
     FROM `Order Details` AS `o0`
     WHERE `o`.`OrderID` = `o0`.`OrderID`) AS `Sum`
 FROM `Orders` AS `o`
@@ -96,7 +96,7 @@ public override async Task Sum_over_truncate_works_correctly_in_projection_2(boo
             AssertSql(
                 """
 SELECT `o`.`OrderID`, (
-    SELECT IIF(SUM(INT(`o0`.`UnitPrice` * `o0`.`UnitPrice`)) IS NULL, 0.0, SUM(INT(`o0`.`UnitPrice` * `o0`.`UnitPrice`)))
+    SELECT IIF(SUM(FIX(`o0`.`UnitPrice` * `o0`.`UnitPrice`)) IS NULL, 0.0, SUM(FIX(`o0`.`UnitPrice` * `o0`.`UnitPrice`)))
     FROM `Order Details` AS `o0`
     WHERE `o`.`OrderID` = `o0`.`OrderID`) AS `Sum`
 FROM `Orders` AS `o`