fix: DNS errors

[jshlbrd]

Description

• Adds an ErrorOnFailure field to the DNS processor

Motivation and Context

Querying DNS with unknown data is likely to result in resolution failures, so this adds a field to explicitly enable errors for certain calls in the processor. This mimics functionality in the Lambda processor and will make its way into other processors through a refactor in 2023.

This also adds a new pattern for querying Team Cymru's Malware Hash Registry.

How Has This Been Tested?

Unit tested via process/example_test.go (change the IP address to something that doesn't exist, such as 127.0.0.2). Tests for the MHR pattern are available internally.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.