ci: Add a “compile the headers” job #1387

1. 
   real-or-random commented at 4:45 pm on July 27, 2023: contributor

   We have a C++ job that checks that all headers compile on their own, but of course, we should test this on C also…

   The example binaries cover some headers, but not by all (e.g., there’s no example for ellswift or prealloc).

2. real-or-random added the label assurance on Jul 27, 2023
3. real-or-random added the label ci on Jul 27, 2023
4. real-or-random added the label build on Jul 27, 2023

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real-or-random

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assurance ci build