some bc routines fail to overwrite the existing data and just create a duplicate BC data

[anilyil]

Description

Some of the internal methods that are supposed to overwrite existing BC information with the new BC information fails to "overwrite" and just end up creating duplicate BC data on these families. As a result, these meshes fail to run in adflow. I think this functionality definitely worked at some point, so I am guessing it will be a relatively minor fix on how we interact with the cgns library.

Steps to reproduce issue

Try to overwrite the BC information on any mesh via overwritebcs. I dont have an exact script ready now, but in the past, I had to first explicitly remove all BCs, and then set the updated ones one by one.

Current behavior

BC info is not overwritten and instead is duplicated.

Expected behavior

BC info should be overwritten so that there is a single BC definition for each face.