C#: Address copilots review comments.

Author: michaelnebel

csharp/ql/src/Language Abuse/SimplifyBoolExpr.ql

@@ -71,6 +71,7 @@ predicate rewriteBinaryExpr(BinaryOperation op, boolean value, string oldPattern
 }
 
 predicate rewriteConditionalExpr(ConditionalExpr cond, string oldPattern, string newPattern) {
+  cond.getCondition().getType() instanceof BoolType and
   cond.getThen().getType() instanceof BoolType and
   cond.getElse().getType() instanceof BoolType and
   (

csharp/ql/test/query-tests/Language Abuse/SimplifyBoolExpr/SimplifyBoolExpr.cs

@@ -46,6 +46,6 @@ void Fn()
         if (true || false) ;
 
         bool? boption = false;
-        if (boption == true) ; // GOOD. Cant be simplified like a regular bool
+        if (boption == true) ; // GOOD. Can't be simplified like a regular bool
     }
 }