Create a revised documentation on Formula linked definitions feature

### Problem description
Currently, we have a documentation, which explains the basic functionality of formula linked definitions : https://docs.hedera.com/guardian/guardian/standard-registry/policies/formula-linked-definitions

### Requirements
Need to revise the existing documentation which would focus on VM0042 methodology showing
- how this feature would be used
- how the formulas can be configured
- Adding screenshots of the formula configuration

### Definition of done
Revising the existing documentation with VM0042 focus.

### Acceptance criteria
Updated and released documentation.