Improve code positions (match + extended assignments) #3415

Job	Run time
EasyCrypt compilation (opam)	1m 14s
EasyCrypt compilation (nix)	1m 38s
Fetch EasyCrypt External Projects Matrix	4s
Check EasyCrypt Libraries (unit)	1m 21s
Check EasyCrypt External Projects (jasmin-eclib, https://github.com/jasmin-lang/jasmin, main, ecl...	1m 56s
Check EasyCrypt Libraries (stdlib)	5m 6s
Check EasyCrypt External Projects (sha3, https://gitlab.com/easycrypt/sha3, next, ., config/tests...	12m 3s
Check EasyCrypt Libraries (examples)	3m 11s
Check EasyCrypt External Projects (cryptobox, https://gitlab.com/fdupress/ec-cryptobox, next, ., ...	2m 22s
Check EasyCrypt External Projects (xsalsa20, https://gitlab.com/fdupress/ec-xsalsa, master, ., co...	1m 44s
Check EasyCrypt External Projects (xmss-acai, https://github.com/MM45/FV-XMSS-EC, master, ., conf...	7m 51s
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...	20m 52s
Check EasyCrypt External Projects (set-status)	2s
Notification	5s
	1h 6m 24s

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