bug: blocking the whole computer in some cases

[J Rt]

Dear all,

I found a blocking behavior in pass. Infos about my system at the
bottom of this email.

To reproduce:

- I am using a smartcard for holding my private GPG key
- when calling pass grep without the card, my system is blocked, I can
do nothing to exit.
- both clicking ok and cancel in the question box asking if I can
insert smartard do not help.
- only way to exit is to 1) insert the smartcard or 2) wait for quite
a while (there seems to be a timeout kicking in after a while (?) ).
cancel, CTRL-C CTRL-D do not help.

- by contrast when doing a pass show for example without the card,
choosing cancel on the box asking to insert the card aborts and I get
my system back.

bash-4.4$ bash --version
GNU bash, version 4.4.20(1)-release (x86_64-pc-linux-gnu)
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
bash-4.4$ lsb_release -a
No LSB modules are available.
Distributor ID:    Ubuntu
Description:    Ubuntu 18.04.4 LTS
Release:    18.04
Codename:    bionicbash-4.4$ gpg --version
gpg (GnuPG) 2.2.4
libgcrypt 1.8.1
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.