Move CI_CONFIG_PATH as a predefined project variable
The purpose of introducing
CI_PROJECT_CONFIG_PATH was to be able to use it in evaluating group level pipeline configuration.
Since group level pipeline configurations are included, and only project variables are currently supported (and available) at the time of
include section evaluation - the variable
CI_CONFIG_PATH will not be available for consumption.
CI_CONFIG_PATHas a predefined project variable.
CI_PROJECT_CONFIG_PATHvariable (check if deprecation is required - the variable was introduced in 13.8)