Testing framework: add asserts in interpreter

There are missing asserts in the interpreter: assert_with_error, assert_some, assert_some_with_error, assert_none, assert_none_with_error.

This MR adds support for those assertions and it closes #1326 (closed) .

• has a changelog entry

changelog/1639745421

+author: er433
+merge_request: '1463'
+title: 'Testing framework: add asserts in interpreter'
+type: added