Make protected field final

Signed-off-by: Sven Strittmatter <sven.strittmatter@iteratec.com>

Author: Weltraumschaf

src/main/java/io/securecodebox/persistence/defectdojo/model/Finding.java

@@ -146,7 +146,7 @@ public enum Severity {
         @JsonAlias("Informational")
         INFORMATIONAL(1);
 
-        long severity;
+        final long severity;
 
         Severity(long severity) {
             this.severity = severity;