Normalize OMB Info section

[derekhouck]

Take the OMB Info fields created by #90732 and normalize them into the following format when output by content-build:

ombInfo: {
  ombNumber,
  expDate,
  resBurden
},

See Slack discussion for more details.

Acceptance Criteria

• Scenario: Normalize OMB Info section
• Given the OMB Info fields are created by Create OMB Info section in Digital Form content type #90732
• When content-build outputs the OMB Info section
• Then the output should be formatted as follows:

  ombInfo: {
    ombNumber,
    expDate,
    resBurden
  }