We've found that we will often have many known-errors with the same help text and fix, but different regex patterns.
This has led to a lot of duplication in our known errors.

Currently, the pattern property only accepts a single string.

        "pattern": {
          "description": "A Regex used to determine if the line is an error.",
          "type": "string"
        }

If we had a patterns property that took an array, we could specify multiple regexes and remove the duplication in our known-errors.

We could replace pattern with patterns, but that would be a breaking change.
The other option would be to accept OneOf either a string or array of strings,
which would be a backward compatible change, but would also leaves us with the awkwardness of having the property named pattern.

        "pattern": {
            "oneOf": [
                {
                    "type": "string"
                },
                {
                    "type": "array",
                    "items": {
                        "type": "string"
                    }
                }
            ]
        }

Obviously, we would need to update the code to loop through and look for any matching patterns.