Proxy Configuration documentation has incorrect example

[kkirsche]

Checklist

• [X] I have searched the Sourcery documentation for the issue, and found nothing
• [X] I have checked there are no open bugs referencing the same bug or problem

Description

https://docs.sourcery.ai/Reference/Configuration/Proxy/#ssl_certs_file

The example:

proxy:
  url: /path/to/cafile.pem

for ssl_certs_file should be:

proxy:
  ssl_certs_file: /path/to/cafile.pem