[BUGFIX] various bugfixes

[pixelmatseriks]

New Pull Request checklist

PR Type

What kind of change does this PR introduce?

• remove unused code and console log
• move required deploymentSites setting from Optional tab to Basic tab
• avoid PHP Warnings caused by undefined array keys
• simplify fileProperties configuration variables
• remove anonymous functions from fileProperties configuration causing fatal error memory size exhausted in "System->Configuration"
• intercept BE errors if no login data has been entered

• [FEATURE] - A new feature
• [BUGFIX] - A bug fix
• [TASK] - Any task, which is not a new feature or bugfix
• [TEST] - Adding missing tests
• [DOC] - Documentation only changes
• [WIP] - Work in progress tag, should not be present when creating pull requests

Breaking change

Does this PR introduce a breaking change?

• Yes
• No

Description