Validate/update ResearchGroup links #450

Describe the issue

Created from comment in purple

Relatedly the links to the RGs may need to be updated. Examples:

The about tab for 4651 shows:
Research group
IP Mobility Optimizations Research Group (MOBOPTS)

Perhaps should link to https://datatracker.ietf.org/rg/mobopts/about/ or https://www.irtf.org/concluded/mobopts.html.

The about tab for 4838 shows:
Research group
Delay-Tolerant Networking (DTNRG)

Perhaps should link to https://datatracker.ietf.org/rg/dtnrg/about/ or https://www.irtf.org/concluded/dtnrg.html

Originally posted by @sginoza in #1310

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