fix: add the encoding to multipple open function calls

[Tiboris]

pylint started to complain about unspecified encoding, thus adding to open functions.

[Tiboris]

No tests were run with this branch yet

[Tiboris]

(venv) [root@kerrigan venv]# mrack eh add
Installed providers: static, beaker, virt, podman, openstack, aws
Adding hosts to /etc/hosts file
Done
(venv) [root@kerrigan venv]# cat /etc/hosts
# Loopback entries; do not change.
# For historical reasons, localhost precedes localhost.localdomain:
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

# Managed by mrack - start
10.30.19.133 aws-tdudlak-9.tdudlak.test
10.0.190.21 r85.mrack.test
10.0.190.218 r9.mrack.test
10.0.199.202 f36.mrack.test
# Managed by mrack - end
(venv) [root@kerrigan venv]# mrack eh --help
Installed providers: podman, openstack, beaker, static, aws, virt
Usage: mrack eh [OPTIONS] COMMAND [ARGS]...

  Commands to update /etc/hosts file.

Options:
  --help  Show this message and exit.

Commands:
  add    Add active hosts to /etc/hosts file.
  clear  Remove all mrack hosts from /etc/hosts file.
(venv) [root@kerrigan venv]# mrack eh clear
Installed providers: virt, openstack, static, beaker, aws, podman
Clearing mrack records in /etc/hosts.
Done
(venv) [root@kerrigan venv]# cat /etc/hosts 
# Loopback entries; do not change.
# For historical reasons, localhost precedes localhost.localdomain:
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6