Revert subtype theory + syntactic sugar for cloning it #3670

Job	Run time
EasyCrypt compilation (opam)	2m 37s
EasyCrypt compilation (nix)	41s
Fetch EasyCrypt External Projects Matrix	2s
Check EasyCrypt Libraries (unit)	3m 0s
Check EasyCrypt External Projects (jasmin-eclib, https://github.com/jasmin-lang/jasmin, main, ecl...	3m 21s
Check EasyCrypt Libraries (stdlib)	6m 25s
Check EasyCrypt External Projects (sha3, https://gitlab.com/easycrypt/sha3, next, ., config/tests...	14m 18s
Check EasyCrypt Libraries (examples)	4m 22s
Check EasyCrypt External Projects (cryptobox, https://gitlab.com/fdupress/ec-cryptobox, next, ., ...	3m 48s
Check EasyCrypt External Projects (xsalsa20, https://gitlab.com/fdupress/ec-xsalsa, ec-main, ., c...	3m 14s
Check EasyCrypt External Projects (xmss-acai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	8m 15s
Check EasyCrypt External Projects (xmss-fsai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	7m 29s
Check EasyCrypt External Projects (sphincsplus, https://github.com/MM45/FV-SPHINCSPLUS-EC, master...	24m 8s
Check EasyCrypt External Projects (set-status)	1s
Notification	2s
	1h 21m 43s

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