Fix(Config): prevent undefined array key from first configuration

[stonebuzz]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

When configuring the plugin for the first time, three warnings were displayed because no values existed yet for non-initialized fields:

This PR prevents these warnings from being triggered during the initial setup.

Screenshots (if appropriate):

[stonebuzz]

need #60 to get CHANGELOG.md file