Update guidance for "IPC connect call failed" scenario

[SeanKilleen]

When following this guide, I received an error message while attempting to add the key in order to install azure-cli.

gpg: connecting dirmngr at '/tmp/apt-key-gpghome.nMumTfhiHO/S.dirmngr' failed: IPC connect call failed
gpg: keyserver receive failed: No dirmngr

Upon further examination, it appears to be an issue with WSL that has a workaround: microsoft/WSL#3286

(I'm behind on Windows feature updates & WSL due to other unfortunate issues during upgrade).

This PR attempts to document the workaround here so that others will have it at the ready. Happy to re-format, update working, etc. as requested.

When applied, this worked for me and allowed me to continue the rest of the installation.

[ghost]

✅ Validation status: passed

File	Status	Preview URL	Details
docs-ref-conceptual/install-azure-cli-apt.md	✅Succeeded	View (azure-cli-latest) View (azure-cli-2017-03-09-profile) View (azure-cli-2018-03-01-hybrid)

For more details, please refer to the build report.

Note: If you changed an existing file name or deleted a file, broken links in other files to the deleted or renamed file are listed only in the full build report.

[sptramer]

Thank you for the pull request, but the issue indicates that the problem has been fixed in Windows 1809, which is no longer an insider build and has been publicly released. Please make sure you follow the WSL troubleshooting steps and update to the latest available build of Windows. If you still experience a problem, file an issue with the WSL team.

(See also #1184, closed for similar reasons.)

[ghost]

✅ Validation status: passed

File	Status	Preview URL	Details
docs-ref-conceptual/install-azure-cli-apt.md	✅Succeeded	View (azure-cli-latest) View (azure-cli-2017-03-09-profile) View (azure-cli-2018-03-01-hybrid)

For more details, please refer to the build report.

Note: If you changed an existing file name or deleted a file, broken links in other files to the deleted or renamed file are listed only in the full build report.

[SeanKilleen]

@sptramer that's really unfortunate. I have been prevented despite over 6 mo of troubleshooting from upgrading my machine from v1709 to even v1803, let alone v1809. I don't see why WSL and azure-cli would only have documentation applicable to the latest feature release of Windows.

I'd humbly suggest that this documentation suggestion remains valid regardless of which version of windows. It adds a workaround for a potential scenario that users could hit.

Are you suggesting that azure-cli is only appropriate for users who have the latest version of windows? If that's the stance, that's fine, but it seems short-sighted.

I looked at docs on-line for roughly 30 minutes before I arrived at the solution, verified it, and put in time to create a PR. I would have loved to have run into the content from #1184 so I could have gotten that time back.