DetailsList: Edge + narrator doesnot say anthing about the sortable detailslist column header

[shsengar]

#10957 # Describe the issue:
Edge+ Narrator is not providing info about the column header if it is sortable or not.

Please provide a reproduction of the issue in a codepen:

1. Open Edge Browser.
2. Go to https://developer.microsoft.com/en-us/fabric#/controls/web/detailslist
3. Start narrator as screen reader.
4. Use Caps+Right Arrow key to navigate to "Name" Column Header(which is sortable). Observe what narrator is saying

Actual behavior:

Narrator is not providing information if the column is functionally sortable.

Expected behavior:

Narrator should announce the header information along with sorting order information. Visually impaired users will find difficulty to know the sorting functionality if its available.

Documentation describing expected behavior

[JasonGore]

Duplicate of #10168, #6646, and #6011. Please search for duplicates before creating issues.