Fix MS_SHOULD_BE_FINAL SpotBugs issue (#169)

Made static fields final to fix SpotBugs MS_SHOULD_BE_FINAL warnings:
- DtlsHelloVerifyRequestProbe.COOKIE_LENGTH_ERROR_VALUE
- QuicRetryPacketProbe.RETRY_TOKEN_LENGTH_ERROR_VALUE
- DefaultRatingLoader.LOGGER
- DefaultRatingLoader.INFLUENCERS_RESOURCE_LOCATION

Author: TLS-Attacker Fix Bot

TLS-Server-Scanner/src/main/java/de/rub/nds/tlsscanner/serverscanner/probe/DtlsHelloVerifyRequestProbe.java

@@ -45,7 +45,7 @@
 
 public class DtlsHelloVerifyRequestProbe extends TlsServerProbe {
 
-    public static Integer COOKIE_LENGTH_ERROR_VALUE = -1;
+    public static final Integer COOKIE_LENGTH_ERROR_VALUE = -1;
 
     private TestResult supportsCookieExchange = TestResults.COULD_NOT_TEST;
     private TestResult hasHvrRetransmissions = TestResults.COULD_NOT_TEST;

TLS-Server-Scanner/src/main/java/de/rub/nds/tlsscanner/serverscanner/probe/quic/QuicRetryPacketProbe.java

@@ -39,7 +39,7 @@
 
 public class QuicRetryPacketProbe extends QuicServerProbe {
 
-    public static Integer RETRY_TOKEN_LENGTH_ERROR_VALUE = -1;
+    public static final Integer RETRY_TOKEN_LENGTH_ERROR_VALUE = -1;
 
     private TestResult hasRetryTokenRetransmissions;
     private TestResult checksRetryToken;

TLS-Server-Scanner/src/main/java/de/rub/nds/tlsscanner/serverscanner/report/rating/DefaultRatingLoader.java

@@ -27,13 +27,13 @@
  */
 public class DefaultRatingLoader {
 
-    private static Logger LOGGER = LogManager.getLogger();
+    private static final Logger LOGGER = LogManager.getLogger();
 
     /**
      * The resource location for the rating influencers XML file. This file contains the
      * configuration for how different properties influence the overall rating of a TLS server.
      */
-    public static String INFLUENCERS_RESOURCE_LOCATION = "rating/influencers.xml";
+    public static final String INFLUENCERS_RESOURCE_LOCATION = "rating/influencers.xml";
 
     /**
      * The default resource template path for recommendation files. Language-specific versions can