add ffi tests & fix ffi #1392

Job	Run time
report	17m 42s
style	41s
build-test (windows-latest, stable, x86_64-pc-windows-msvc, true)	15m 51s
build-test (macos-latest, stable, x86_64-apple-darwin, true)	9m 35s
build-test (ubuntu-20.04, stable, x86_64-unknown-linux-gnu, true)	8m 54s
build-test (ubuntu-22.04, stable, x86_64-unknown-linux-gnu, true)	8m 51s
build-test (ubuntu-22.04, stable, i686-unknown-linux-gnu, true)	11m 25s
build-test (ubuntu-22.04, nightly, wasm32-unknown-unknown, true, --no-default-features, --no-run ...	6m 11s
build-test (ubuntu-22.04, 1.77, x86_64-unknown-linux-gnu)	1m 29s
build-test (ubuntu-22.04, beta, x86_64-unknown-linux-gnu)	5m 1s
build-test (ubuntu-22.04, nightly, x86_64-unknown-linux-gnu, true, miri)	6m 48s
release	0s
logtalk-test	0s
	1h 32m 28s

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