New linting rule - Description metadata

I'd like the linter to provide warnings where;
**Parameters have been declared with no description metadata**

This would help ensure quality of the bicep code that is produced. It doesn't obviously guarantee good quality descriptions, but as a linting warning it is a good prompt for bicep rookies.

As a natural extension, the other objects that support description metadata should also be able to have this linting rule specified.
Modules/Variables/Resources have been declared with no description metadata

The issue names no files, tests, or entry points; start by locating existing linter rules and the handling of description metadata in the Bicep codebase. Confirm coverage for parameters, modules, variables, and resources, then verify warnings and rule configuration with the relevant linter tests.

Written by the indexing model from the issue text.