The defaulting should only be done after submission phase

[scarlett2018]

• The defaulting should only be done after submission phase.
  the current validation updated the fields that is empty with default values, should not change users original form.
  • check all the fields that has this problem and then rank the priority
• And we should not change user already specified values in any phase.

Originally posted by @scarlett2018 in #3823 (comment)

[debuggy]

solution:

1. A new page for users who imports an exact config and directly submit it to api (quick access ui for api), enable user to edit config in an editor and do not add extra change.
2. If user submit job through wizard, some changes are inevitable. But still not add more properties and leave the null values for job protocol.

[yqwang-ms]

Where is the "new page for users"?