fix: email notifications with wrong submission id

[g-tejas]

Problem

For email notifications being sent out by encrypt mode form submissions, the submission ID and the creation date correspond with the form's id and creation date respectively.

Solution

Since the submission id and created time is only generated under _createSubmission, we have to move the MailSubmission.sendSubmissionToAdmin to after these are generated to ensure the created time is consistent with what's shown in the last page.

Breaking Changes

• No - this PR is backwards compatible

Tests

• 1. Create a storage mode form
• 2. Add admin emails in the "Email notifications" tab
• 3. Open the form to public
• 4. Make a submission and note the submission ID and the created timestamp
• 5. Navigate to email
• 6. Observe that the email notification contains the ID and timestamp as what's displayed in the last page.

[KenLSM]

LGTM!