Adds raw column to all ci variable tables

What does this MR do and why?

Adds the raw attribute to the following tables: CiPipelineVariables
CiGroupVariables
CiInstanceVariables
CiJobVariables
CiPipelineScheduleVariables
CiVariables

This work is part 1/2 of: #361934 (closed) in order to make it possible to set variables as non-expanded.

We decided to default the variables to not be expanded, as users are often surprised when this happens.

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