Slash character is not considered as a separator

[Dekedro]

Command:

$ a=/root; b=test; export a b
$ echo '$a/$b' | envsubst a b

Expected output: "/root/test" Actual output: "$a/$b"

Looks like characters strpbrk accepts should include "/": https://github.com/kaniini/envsubst/blob/3061277c9d957f970b0922282fd7ccab7cda3414/envsubst.c#L187