Improve code positions (match + extended assignments) #3429

Job	Run time
EasyCrypt compilation (opam)	1m 12s
EasyCrypt compilation (nix)	1m 20s
Fetch EasyCrypt External Projects Matrix	8s
Check EasyCrypt Libraries (unit)	1m 15s
Check EasyCrypt External Projects (jasmin-eclib, https://github.com/jasmin-lang/jasmin, main, ecl...	1m 55s
Check EasyCrypt Libraries (stdlib)	5m 6s
Check EasyCrypt External Projects (sha3, https://gitlab.com/easycrypt/sha3, next, ., config/tests...	12m 30s
Check EasyCrypt Libraries (examples)	3m 4s
Check EasyCrypt External Projects (cryptobox, https://gitlab.com/fdupress/ec-cryptobox, next, ., ...	2m 23s
Check EasyCrypt External Projects (xsalsa20, https://gitlab.com/fdupress/ec-xsalsa, master, ., co...	1m 45s
Check EasyCrypt External Projects (xmss-acai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	7m 55s
Check EasyCrypt External Projects (xmss-fsai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	6m 55s
Check EasyCrypt External Projects (sphincsplus, https://github.com/MM45/FV-SPHINCSPLUS-EC, master...	21m 20s
Check EasyCrypt External Projects (set-status)	3s
Notification	4s
	1h 6m 55s

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