Create receiver filter best practices and guidance document

[GilmoreA6]

Problem statement

Without written best practices and standards for how filters should be created and tested, it is difficult to know what filters are doing. By creating and documenting a standard way of creating and testing filters we can be sure that filters are behaving as expected and that queries can be written to troubleshoot production issues

Acceptance criteria

• [ ] Document is created in repo and link to receivers.md documenting detailing how to create and test filters.
• [ ] The following situations are covered in the filter document - how to filter positive/negative results - how to filter results on other STLT assigned criteria such as testing method or facility type - how to test condition filter is filtering out unwanted conditions