scopes: with-types use Ast_typed.environment instead of rebuilding a partial program

quick test with time

time ligo get-scope src/test/contracts/multisig.mligo --format=dev --with-types

this version

real    0m0.315s
user    0m0.296s
sys     0m0.020s

dev

real    0m1.698s
user    0m0.443s
sys     0m0.133s

• has a changelog entry