git access issues in some CI jobs

Hi. A number of CI jobs failed over the weekend. An interesting new failure mode that I don't see noted in other active tickets is:

  Running command git clone --filter=blob:none --quiet https://gitlab.torproject.org/tpo/core/chutney.git /tmp/pip-req-build-r3qn3cv9
  fatal: unable to access 'https://gitlab.torproject.org/tpo/core/chutney.git/': Failed to connect to gitlab.torproject.org port 443 after 134918 ms: Couldn't connect to server

and similar.

For example

• https://gitlab.torproject.org/tpo/core/arti/-/jobs/1071290
• https://gitlab.torproject.org/tpo/core/arti/-/jobs/1070888
• https://gitlab.torproject.org/tpo/core/arti/-/jobs/1069653

The failure probability for each individual job is fairly low but our pipeline has 45 jobs.