ARTEMIS-5720: Resolve issues reported by sonarqube analysis

[GChuf]

No description provided.

[andytaylor]

@GChuf what was the reason for 'Remove shorthand CSS property for background' ? all the rest make sense.

[GChuf]

If i understand this correctly:
https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_cascade/Shorthand_properties
all properties not defined in shorthand property (background) will fall back to defaults - so the best way to do it is to either include everything in the shorthand property, or use longhand properties - but not both