docs: Add VOLK doc build to CI #290

Job	Run time
Build on ubuntu-20.04 g++-7	50s
Build on ubuntu-20.04 g++-8	51s
Build on ubuntu20.04 aarch64 g++-8	7m 8s
Build on ubuntu-latest g++-9	1m 1s
Build on ubuntu20.04 aarch64 g++-9	7m 12s
Build on ubuntu-latest g++-10	59s
Build on ubuntu20.04 aarch64 g++-10	6m 52s
Build on ubuntu-20.04 clang-7	59s
Build on ubuntu22.04 aarch64 g++-12	7m 43s
Build on ubuntu-20.04 clang-8	57s
Build on ubuntu20.04 aarch64 clang-9	11m 35s
Build on ubuntu-20.04 clang-9	1m 4s
Build on ubuntu20.04 aarch64 clang-10	11m 35s
Build on ubuntu-20.04 clang-10	55s
Build on ubuntu22.04 aarch64 clang-14	11m 1s
Build on ubuntu-20.04 clang-11	49s
Build on ubuntu22.04 armv7 g++	7m 12s
Build on ubuntu-latest clang-12	1m 3s
Build on ubuntu22.04 ppc64le g++-12	7m 45s
Build on ubuntu-latest clang-13	1m 5s
Build on ubuntu22.04 s390x g++-12	6m 12s
Build on ubuntu-latest clang-14	1m 8s
Build on ubuntu22.04 riscv64 g++-12	6m 19s
Build VOLK docs	18s
build-macos	1m 50s
Build static on ubuntu-latest	1m 9s
build-windows	2m 26s
	1h 47m 58s

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