Add regression test for watertightness #1627

Job	Run time
cargo check (msrv) (wasm32)	49s
cargo check (aarch64-android)	24s
cargo clippy (windows-latest)	4m 40s
cargo check (msrv) (windows-latest)	2m 32s
cargo clippy (macos-latest)	1m 13s
cargo clippy (wasm32)	1m 15s
cargo check (msrv) (macos-latest)	47s
cargo doc	24s
cargo clippy (ubuntu-latest)	1m 29s
cargo check (msrv) (ubuntu-latest)	44s
cargo fmt	26s
Prime LFS Cache	4s
cargo test (wasm32)	23s
typos	4s
cargo test (windows-latest)	2m 29s
cargo test (macos-latest)	1m 49s
cargo test (ubuntu-latest)	3m 13s
	22m 45s

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