[enhancement]: Allow variable groups to be inherited from calling yaml to template yaml

[KarthicPortal]

Task name

Allow variable groups to be inherited from calling yaml to template yaml

Describe your feature request here

With current setup, we have to add variables one by one either via templates variables.yaml or parameters from calling yaml file to the template yaml. This becomes complex if we go for multi stage pipeline with multiple variables for each stage. So, please support the variable groups inheritance from calling yaml to template yaml.