fix: failed ensures should block submission

[LinHuiqing]

Problem

Bug was introduced by #6595 where failing ensures do not return early if a response has already been sent.

Solution

Breaking Changes

• No - this PR is backwards compatible

Bug Fixes:

• Failing ensures should return early.

Tests

Check that storage mode submissions will be gated by ensures.

• ensureIsPublicForm:
  • Go to a public form.
  • Close the form on the admin portal.
  • Make a submission. Submission should not succeed.
    • Error should be shown to client.
    • New submission should not show up on DB
• ensureValidCaptcha:
  • Go to a public form with captcha disabled.
  • Enable captcha on the admin portal.
  • Make a submission. Submission should not succeed.
    • Error should be shown to client.
    • New submission should not show up on DB
• ensureFormWithinSubmissionLimits:
  • Go to a public form with a submission limit. The form should still be open at this point.
  • On the DB, edit the submission limit so that it is less than or equal to the number of existing submissions.
  • Make a submission. Submission should not succeed.
    • Error should be shown to client.
    • New submission should not show up on DB

[tshuli]

lgtm