CI updates, including a fix for a test script.

7 patches for repository http://darcs.net/screened:

patch fda4fc484ce8a014a9a63e5812510e1c67c91122
Author: Ben Franksen <ben.franksen@online.de>
Date:   Wed Nov  3 12:38:42 CET 2021
  * ci: redesign caching of cabal store and dist-newstyle

patch a3390168fe4165b78fab0ba0b8b6fb2369bd1a10
Author: Ben Franksen <ben.franksen@online.de>
Date:   Tue Nov  2 17:12:52 CET 2021
  * fix for tests/network/external.sh failure on ubuntu with ghc-8.10

  This also slightly re-organizes the script to make it easier to understand
  what's going on.

patch 413c4d808ca2b9b67ed9a7b967ca2cf090d98cc1
Author: Ben Franksen <ben.franksen@online.de>
Date:   Tue Nov  2 12:28:45 CET 2021
  * ci: actions/setup-haskell -> haskell/actions/setup

  The former is no longer maintained. Also let haskell/actions/setup choose
  the precise versions and specify only the first two version components. This
  is more robust and allows us to remove the macOS-10.15/ghc-8.10.4 exception.

patch f66c704e58c20225a476a4e53b8254915e7ed46b
Author: Ben Franksen <ben.franksen@online.de>
Date:   Wed Nov  3 12:34:21 CET 2021
  * ci: always use the "latest" version of cabal

  Including several cabal versions in the build matrix is problematic for
  caching and blows up resource usage unreasonably. Besides, cabal-3.2 cannot
  be used with ghc > 8.10, which would then require more exceptions.

patch 51b14cf03910bd52257bfe91f96a8bc9b9028605
Author: Ben Franksen <ben.franksen@online.de>
Date:   Tue Nov  2 12:55:21 CET 2021
  * ci: add ghc-9.0 to the matrix

patch 2df810e58b4c63ffe4efbb62b9de8322db4b9901
Author: Ben Franksen <ben.franksen@online.de>
Date:   Wed Nov  3 17:35:05 CET 2021
  * ci: install lighttpd before running tests on linux

  Otherwise most of the network tests are skipped.

patch 3c251b4415200bdf69543278b59f2adc7fb261d8
Author: Ben Franksen <ben.franksen@online.de>
Date:   Wed Nov  3 17:37:57 CET 2021
  * ci: add macOS-11 and windows-2022 to matrix

Attachments

• ci_-redesign-caching-of-cabal-store-and-dist_newstyle.dpatch
• patch-preview.txt

Looks good - accepting quickly as CI is breaking for me on reviewed :-)

[WSL2 running Ubuntu - there were two tests that generate temporary shell 
scripts not starting with #!/bin/sh - for some reason that breaks in my 
environment but apparently not elsewhere.]

Sorry, disregard the previous message, posted it to the wrong issue.