[FEATURE REQ] Optimize directory scanning with bicep modules

### Please describe the feature or suggestion.

The performance of scanning a directory that contains bicep templates with modules that refer to other templates in the same directory could be improved. After scanning a bicep template with modules, subsequent evaluations of those same module files can be skipped, and their evaluations pulled from an evaluation cache.

### Additional context

See [this PR comment thread ](https://github.com/Azure/template-analyzer/pull/290#discussion_r979112446) for more context.