Patients without identified sex show up as null or undefined on patient reports

[jkleinsc]

Expected behavior:
When running patient reports such as admission report which groups counts by sex, those patients without a sex filled out in the demographic information show up as "Sex Not Entered" or a similar label
Actual behavior:
In patient reports such as admission report which groups counts by sex, patients without a sex filled out in the demographic information show up as null or undefined
Steps to reproduce:

1. Create a new patient, but leave the Sex field empty.
2. Admit that new patient
3. Run the admissions detail patient report
   Screenshots (if applicable):

OS and Browser:
All