The help_sections.rs file was added to the tarball only as a quick hack.
There is a cyclic dependency between docs and fish:
"fish_indent" via "crates/build-man-pages" depends on "doc_src/".
So every "touch doc_src/foo.rst && ninja -Cbuild sphinx-docs"
re-builds fish.
In future "fish_indent" should not depend on "crates/build-man-pages".
Until then, a following commit wants to break this cyclic dependency
in a different way: we won't embed man pages (matching historical
behavior), which means that CMake builds won't need to run
sphinx-build.
But sphinx-build is also used for extracting help sections.
Also, the fix for #12082 will use help sections elsewhere in the code.
Prepare to remove the dependency on doc_src by committing the help
sections (we already do elsewhere).
This test is the one with the longest runtime. Splitting the two targets into
separate tests allows them to run in parallel, which can speed up the tests.
