Fix some parsons tests

tests/input_parsons_test.php

@@ -91,11 +91,11 @@ public function test_validate_parsons_state_input(): void {
         $state = $el->validate_student_response(['sans1' => '[[{"used":[[[]]],"available":["aGVsbG8=","d29ybGQ="]},0]]'],
             $options, $ta,
                 new stack_cas_security());
-        print_r($state);
+
         $this->assertEquals(stack_input::VALID, $state->status);
         $this->assertEquals('', $state->note);
         $this->assertEquals('', $state->errors);
-        $this->assertEquals('"[[{\"used\":[[[]]],\"available\":[\"aGVsbG8=\",\"d29ybGQ=\"]},0]]"', $state->contentsmodified);
+        $this->assertEquals('"[{\"used\":[[[]]],\"available\":[\"aGVsbG8=\",\"d29ybGQ=\"]},0]"', $state->contentsmodified);
         $this->assertEquals('\[ \text{[[{"used":[[[]]],"available":'
                 . '["hello","world"]},0]]} \]', $state->contentsdisplayed);
         $this->assertEquals('',
@@ -193,7 +193,7 @@ public function test_validate_parsons_whitespace(): void {
         $state = $el->validate_student_response(['sans1' => ' [[{"used":[[[]]],"available":["aGVsbG8=","d29ybGQ="]},0]]  '],
                 $options, $ta, new stack_cas_security());
         $this->assertEquals(stack_input::VALID, $state->status);
-        $this->assertEquals('" [[{\"used\":[[[]]],\"available\":[\"aGVsbG8=\",\"d29ybGQ=\"]},0]]  "',
+        $this->assertEquals('" [{\"used\":[[[]]],\"available\":[\"aGVsbG8=\",\"d29ybGQ=\"]},0]  "',
             $state->contentsmodified);
         $this->assertEquals('\[ \text{[[{"used":[[[]]],"available":'
                 . '["hello","world"]},0]]} \]', $state->contentsdisplayed);