Add UNSPECIFIED as a output from CodeChecker

CodeChecker can output UNSPECIFIED as a warning level when it does not know the level fully. For example here: https://github.com/Ericsson/codechecker/blob/36e6ad8c9a7381545983e89ebe756f6493bcd503/web/client/codechecker_client/report_type_converter.py#L86

src/main/java/edu/hm/hafner/analysis/parser/CodeCheckerParser.java

@@ -21,7 +21,7 @@
 public class CodeCheckerParser extends LookaheadParser {
     private static final long serialVersionUID = -3015592762345283582L;
     private static final String CODE_CHECKER_DEFECT_PATTERN =
-            "^\\[(?<severity>CRITICAL|HIGH|MEDIUM|LOW)\\] (?<path>.+):(?<line>\\d+):(?<column>\\d+): (?<message>.*?) \\[(?<category>[^\\s]*?)\\]$";
+            "^\\[(?<severity>UNSPECIFIED|CRITICAL|HIGH|MEDIUM|LOW)\\] (?<path>.+):(?<line>\\d+):(?<column>\\d+): (?<message>.*?) \\[(?<category>[^\\s]*?)\\]$";
 
     /**
      * Creates a new instance of {@link CodeCheckerParser}.