Remove country specification from default certificate (#5756)

BouncyCastle now validates the X.520 country-code (2.5.4.6) attribute
against ISO 3166-1, which requires exactly 2 characters.
This no longer allows "C=None".

Signed-off-by: Holger Friedrich <mail@holger-friedrich.de>

Author: holgerfriedrich

bundles/org.openhab.core.io.jetty.certificate/src/main/java/org/openhab/core/io/jetty/certificate/internal/CertificateGenerator.java

@@ -75,7 +75,7 @@ public class CertificateGenerator implements BundleActivator {
     private static final String KEY_FACTORY_TYPE = "EC";
     private static final String CONTENT_SIGNER_ALGORITHM = "SHA256withECDSA";
     private static final String CERTIFICATE_X509_TYPE = "X.509";
-    private static final String X500_NAME = "CN=openhab.org, OU=None, O=None, L=None, C=None";
+    private static final String X500_NAME = "CN=openhab.org, OU=None, O=None, L=None";
 
     private Logger logger;