drop shellapi #51

Job	Run time
config	8s
fuzz smoke test	35s
win+VS build	0s
linux32 (daald/ubuntu32:xenial)	5m 36s
sparse	3m 11s
static-analysis	3m 40s
linux-musl (alpine)	5m 35s
win build	3m 55s
pedantic (fedora)	2m 2s
documentation	3m 21s
linux-asan-ubsan (ubuntu-latest)	5m 30s
linux-gcc (ubuntu-20.04)	5m 46s
linux-gcc-default (ubuntu-latest)	5m 47s
linux-leaks (ubuntu-latest)	5m 30s
linux-reftable (ubuntu-latest)	5m 52s
linux-reftable-leaks (ubuntu-latest)	5m 27s
linux-sha256 (ubuntu-latest)	5m 46s
linux-TEST-vars (ubuntu-20.04)	5m 47s
osx-clang (macos-13)	5m 26s
win+VS test	0s
osx-gcc (macos-13)	5m 20s
osx-reftable (macos-13)	5m 33s
win test	0s
	1h 29m 47s

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