change test duration to 2 seconds

Author: davidmoten

src/test/java/rx/internal/operators/OperatorConcatTest.java

@@ -797,7 +797,7 @@ public void onNext(Integer t) {
 
     @Test//(timeout = 100000)
     public void concatMapRangeAsyncLoopIssue2876() {
-        final long durationSeconds = 10;
+        final long durationSeconds = 2;
         final long startTime = System.currentTimeMillis();
         for (int i = 0;; i++) {
             //only run this for a max of ten seconds
@@ -823,4 +823,5 @@ public Observable<Integer> call(Integer t) {
             assertEquals((Integer)999, ts.getOnNextEvents().get(999));
         }
     }
+    
 }