Fix compiler warnings.

FossilOrigin-Name: e9955c0e14d13ba1411f013acb4979958dae2516

src/test1.c

@@ -3661,7 +3661,7 @@ static int test_prepare_v2(
     zCopy = malloc(bytes);
     memcpy(zCopy, zSql, bytes);
   }else{
-    int n = strlen(zSql) + 1;
+    int n = (int)strlen(zSql) + 1;
     zCopy = malloc(n);
     memcpy(zCopy, zSql, n);
   }