This PR aims to support the dynamic values for labels in the
NodeFeatureRule CRD, it would offer more flexible labeling for users.
To achieve this, we check whether label value starts with "@", and if
it's the case, we will get the value of the feature value, and update
the value of the label with the feature value.
Signed-off-by: AhmedGrati <ahmedgrati1999@gmail.com>
Add tests covering the basic functionality of NodeFeatureRule objects,
covering different feature types ("flag features", "attribute features"
and "instance features") as well as backreferencing (using the output of
previously run rules) and templating. The test relies on the "fake"
feature source and its default configuration.