Inability to login via CLI

Hi.

I have issues when trying to `keybase login` on my machine. The error is as follows:

```
keybase login justinabrahms
▶ ERROR in Login

Sorry, your account is already established with a PGP public key, but this
utility cannot access the corresponding private key. You need to prove
you're you. We suggest one of the following:

- install GPG and put your PGP private key on this machine and try again
- reset your account and start fresh: https://keybase.io/#account-reset
```

Various versions:

```
$ keybase version
Client: 4.4.1-20190910185008+b5f8897c2a
Service: 4.4.1-20190910185008+b5f8897c2a

$ 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
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Home: /home/justin/.gnupg
Supported algorithms:
Pubkey: RSA, ELG, DSA, ECDH, ECDSA, EDDSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,
CAMELLIA128, CAMELLIA192, CAMELLIA256
Hash: SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2
```

The key exists:

```
$ gpg --list-keys my-email
pub rsa4096 2013-06-28 [SC]
E0B7AA7C81E5BEC7991EFA4E320E47C9795AD0D6
uid [ultimate] Justin Abrahms (Formerly Lilly)
uid [ultimate] [jpeg image of size 9119]
sub rsa4096 2013-06-28 [E]
```

When I run `keybase log send`, I have the log ID is 344fc8a3ec006317fb594f1c

Start by reproducing `keybase login justinabrahms` with the reported Keybase and GnuPG versions, then review the log identified by ID 344fc8a3ec006317fb594f1c. Compare the CLI's private-key detection with the available key shown by `gpg --list-keys`; done means login succeeds without the missing-private-key error.

Written by the indexing model from the issue text.