curl: add some key reverse-dependencies to passthru.tests

[risicle]

Description of changes

Packages that have a large reverse dependency set are hard to test because a full rebuild is infeasible. But on the other hand, it's tricky for reviewers to remember which reverse dependencies of a particular package are particularly important to ensure are working or are known to be particularly sensitive to changes in the depended package.

Therefore it makes sense to add a small selection of such packages to passthru.tests. Done here for curl. Concentrated on bindings to the library which may be sensitive to changes in the library interface and also have their own test suites covering curl operation.

Other PRs in this vein:

• imlib2: add some key reverse-dependencies to passthru.tests #167079
• python3Packages.twisted: add some key reverse dependencies to passthru.tests #168407
• freetype: add some key reverse dependencies to passthru.tests #167092
• re2: add some key reverse dependencies to passthru.tests #167099
• re2c: add some key reverse dependencies to passthru.tests #168921

Also see #170828 to get curl's own tests enabled.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 22.05 Release Notes (or backporting 21.11 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.