fix: Use 'Working Group' or 'BOF' on session notification messages

[russhousley]

fix: Use 'Working Group' or 'BOF' on session notification messages (fixes #11028)

[cabo]

Should this have code for Research Groups?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.58%. Comparing base (8dbc1bc) to head (dfa4bc0).
⚠️ Report is 33 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11235      +/-   ##
==========================================
+ Coverage   88.52%   88.58%   +0.05%     
==========================================
  Files         334      333       -1     
  Lines       45102    44672     -430     
==========================================
- Hits        39927    39573     -354     
+ Misses       5175     5099      -76     

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[rjsparks]

Should this have code for Research Groups?

Elaborate?

The code already handles research groups.

This PR makes how it handles RG better by changing the template to say "Group" instead of "Working Group" so messages like the one at https://mailarchive.ietf.org/arch/msg/cfrg/pkYDkGimEuhpwTraZUNfryesDhU/ won't say Working Group Name: Crypto Forum - it will say Group Name: Crypto Forum

The the "on behalf of" branch of the code touched already handled RG gracefully, and this doesn't change that.

Having the group type called out in the context of this mail isn't actually needed.

[cabo]

The code already handles research groups.

This PR makes how it handles RG better by changing the template to say "Group" instead of "Working Group" so messages like the one at https://mailarchive.ietf.org/arch/msg/cfrg/pkYDkGimEuhpwTraZUNfryesDhU/ won't say Working Group Name: Crypto Forum - it will say Group Name: Crypto Forum

Great, so that dissonance of seeing 'working group" there is gone.

Thank you!