Hashicorp keysource should be configurable

[mbloch1986]

Hello

The import of the hashicorp certificate from keybase.io is failing atm Error message:

[root@dbda206cfe39 workspace]# wget -O- https://keybase.io/hashicorp/pgp_keys.asc?fingerprint=91a6e7f85d05c65630bef18951852d87348ffc4c | gpg --import
--2020-06-03 08:51:01--  https://keybase.io/hashicorp/pgp_keys.asc?fingerprint=91a6e7f85d05c65630bef18951852d87348ffc4c
[..]
ERROR: cannot verify keybase.io's certificate, issued by ‘/C=GB/ST=Greater Manchester/L=Salford/O=Sectigo Limited/CN=Sectigo RSA Domain Validation Secure Server CA’:
  Issued certificate has expired.
To connect to keybase.io insecurely, use `--no-check-certificate'.
gpg: no valid OpenPGP data found.
gpg: Total number processed: 0

Instead of relying on the hardcoded key source https://keybase.io/hashicorp/pgp_keys.asc?fingerprint=91a6e7f85d05c65630bef18951852d87348ffc4c (https://github.com/inkblot/puppet-hashicorp/blob/master/manifests/init.pp#L13) wouldn't it be a good idea to make this paramter configurable, this would allow us to pass a file path as source.

Any opinions about this ?