Add logging information

Author: res0nance

src/main/java/jenkins/plugins/git/GitSCMFileSystem.java

@@ -286,12 +286,14 @@ public SCMFileSystem build(@NonNull Item owner, @NonNull SCM scm, @CheckForNull
             UserRemoteConfig config = gitSCM.getUserRemoteConfigs().get(0);
             BranchSpec branchSpec = gitSCM.getBranches().get(0);
             String remote = config.getUrl();
+            LogTaskListener listener = new LogTaskListener(LOGGER, Level.FINE);
             if (remote == null) {
+                listener.getLogger().println("Git remote url is null");
+                listener.close();
                 return null;
             }
             String cacheEntry = AbstractGitSCMSource.getCacheEntry(remote);
             Lock cacheLock = AbstractGitSCMSource.getCacheLock(cacheEntry);
-            TaskListener listener = new LogTaskListener(LOGGER, Level.FINE);
             cacheLock.lock();
             try {
                 File cacheDir = AbstractGitSCMSource.getCacheDir(cacheEntry);