[migrate:execute] Migrate content from non-database source

[langelhc]

[migrate:execute] Migrate content from non-database source

Problem/Motivation

Trying to setup and execute a migration from a non-database source the user is prompted to provide credentials to the database server.

Details to include:
This is needed to setup/execute migrations from xml/csv/json files without provide database credentials.

How to reproduce

• drupal migrate:setup
• drupal migrate:execute my-migration

Details to include:

• Drupal version: 8.x.
• Console version: 1.0.2
• Console Launcher version: 1.0.2

Solution

Add parameter to determine a non-database source.

[langelhc]

WIP on #3538