add hpc.social job board (USRSE#1462)

* add hpc.social job board

Add a reference to the hpc.social jobs board.
Discussed and OK in #job-post-team channel.

* Update _data/job-boards.yml

Co-authored-by: Daniel S. Katz <[email protected]>

---------

Co-authored-by: Daniel S. Katz <[email protected]>

Author: Chad Dougherty

_data/job-boards.yml

@@ -5,4 +5,5 @@ boards:
     url: https://carpentries.topicbox.com/groups/opportunities
   - name: Academic Data Science Alliance Jobs
     url: https://academicdatascience.org/jobs
-
+  - name: High Performance Computing (HPC) Jobs from hpc.social
+    url: https://hpc.social/jobs/