Prod Submission Issue

## The issue
SFU reported a submission issue: Large sequencing files submission, 133 files being submitted, UI taking a long time to respond, could be because of md5sum check(happens in browser via react library, taking memory from browser), also the ui responds slowly to large files.
At final submission, only partial files(130) are committed, not sure if it’s an UI issue or user error.

## Task
1. UI changes - Add instructions to the submission page. https://github.com/imicroseq/portal-ui/pull/522
2. change the submission API: https://github.com/imicroseq/submission-service/pull/26
3. Add a Confirm button on UI: https://github.com/imicroseq/portal-ui/pull/523
4. To delete unwanted and committed records, we need this api in maestro: https://github.com/overture-stack/maestro/issues/296