fix(pass): completion for multiple repositories

[ombre8]

Standards checklist:

• The PR title is descriptive.
• The PR doesn't replicate another PR which is already open.
• I have read the contribution guide and followed all the instructions.
• The code follows the code style guide detailed in the wiki.
• The code is mine or it's from somewhere with an MIT-compatible license.
• The code is efficient, to the best of my ability, and does not waste computer resources.
• The code is stable and I have tested it myself, to the best of my abilities.
• If the code introduces new aliases, I provide a valid use case for all plugin users down below.

Changes:

• changed pass plugin according to https://lists.zx2c4.com/pipermail/password-store/2019-January/003502.html I don't know why this wasn't merged upstream, but this fixes the completion if you use multiple repositories

Other comments:

without the fix workpass secre[tab] works but workpass edit secre[tab] would search the default pass directory for that secret

[carlosala]

LGTM!

[carlosala]

Thanks!