swift-init all start throws error for missing config

[Al Delgado]

Executing `swift-init all start` as instructed results in the error:

```
Unable to load internal client from config: '/etc/swift/internal-client.conf' ([Errno 2] No such file or directory: '/etc/swift/internal-client.conf')
```

I got around this by:

```
curl -o /etc/swift/internal-client.conf https://opendev.org/openstack/swift/raw/branch/master/etc/internal-client.conf-sample
```

A lucky guess on my part. It was either get the file, or find out what config pulls that in and comment that stuff out.

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-----------------------------------
Release: 2.29.2.dev5 on 2019-05-23 10:53:31
SHA: 00763d5a00896a28b6665e88f9ea4d4a9fb50a83
Source: https://opendev.org/openstack/swift/src/doc/source/install/finalize-installation-ubuntu-debian.rst
URL: https://docs.openstack.org/swift/yoga/install/finalize-installation-ubuntu-debian.html