Fix expected error message

testing/offset.test

@@ -90,26 +90,26 @@ do_execsql_test_on_specific_db {:memory:} offset-expr-int-and-string {
 
 do_execsql_test_in_memory_error_content offset-expr-cannot-be-cast-losslessly-1 {
   SELECT 1 LIMIT 3 OFFSET 1.1;
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}
 
 do_execsql_test_in_memory_error_content offset-expr-cannot-be-cast-losslessly-2 {
   SELECT 1 LIMIT 3 OFFSET 1.1 + 2.2 + 1.9/8;
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}
 
 # Return error as float in expression cannot be cast losslessly
 do_execsql_test_in_memory_error_content offset-expr-cannot-be-cast-losslessly-3 {
   SELECT 1 LIMIT 3 OFFSET 1.1 + 'a';
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}
 
 do_execsql_test_in_memory_error_content offset-expr-invalid-data-type-1 {
   SELECT 1 LIMIT 3 OFFSET 'a';
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}
 
 do_execsql_test_in_memory_error_content offset-expr-invalid-data-type-2 {
   SELECT 1 LIMIT 3 OFFSET NULL;
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}
 
 # Expression below evaluates to NULL (string → 0)
 do_execsql_test_in_memory_error_content offset-expr-invalid-data-type-3 {
   SELECT 1 LIMIT 3 OFFSET 1/'iwillbezero ;-; ';
-} {"the value in register cannot be cast to integer"}
+} {"datatype mismatch"}