Fix: Skip export of compressed Archive entries

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/utils/ArchivePacker.java

@@ -30,7 +30,7 @@ public class ArchivePacker {
             tmpDir = Files.createTempDirectory("zipTmp");
             tmpDir.toFile().deleteOnExit();
             for (CityGmlZipEntry entry : archive.getEntries()) {
-                if (entry.getErrorType() != null){
+                if (entry.getErrorType() != null || !entry.isDecompressed()) {
                     continue;
                 }
                 CityDoctorModel model = entry.getModel();