check repository

Author: vladak

opengrok-indexer/src/test/java/org/opengrok/indexer/history/FileHistoryCacheTest.java

@@ -38,6 +38,7 @@
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
+import java.net.URL;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -103,7 +104,9 @@ static void setUpClass() throws Exception {
     @BeforeEach
     void setUp() throws Exception {
         repositories = new TestRepository();
-        repositories.create(getClass().getResource("/repositories"));
+        URL url = getClass().getResource("/repositories");
+        assertNotNull(url);
+        repositories.create(url);
 
         // Needed for HistoryGuru to operate normally.
         env.setRepositories(repositories.getSourceRoot());