Removed checks that ThreadContext.withContextPropagation(CS/CF) canno…

…t run async actions without executor

Because it really depends if there is a default executor, and we have tests for both cases elsewhere (with/without)

tck/src/main/java/org/eclipse/microprofile/context/tck/ThreadContextTest.java

@@ -946,14 +946,6 @@ public void withContextCaptureDependentCompletableFuturesRunWithContext()
             // guarantees about context propagation
             CompletableFuture<Integer> unmanagedStage5 = unmanagedStage1.thenApply(i -> i / 2);
 
-            try {
-                CompletableFuture<Integer> stage6 = stage4.thenApplyAsync(i -> i / 5);
-                Assert.fail("Should not be able to create async completion stage because withContextCapture provides no executor. " + stage6);
-            }
-            catch (UnsupportedOperationException x) {
-                // test passes, CompletableFutures from withContextCapture are not backed by an executor
-            }
-
             Label.set("withContextCapture-CompletableFuture-test-label-E");
 
             unmanagedStage1.complete(1010);
@@ -1065,14 +1057,6 @@ public void withContextCaptureDependentCompletionStagesRunWithContext() throws E
                 return i - 2345;
             }, labelContextExecutor); // supplied executor runs the action, but does not determine context propagation
 
-            try {
-                CompletionStage<Void> stage5 = stage4.thenAcceptAsync(i -> System.out.println("This should not ever run."));
-                Assert.fail("Should not be able to create async completion stage because withContextCapture provides no executor. " + stage5);
-            }
-            catch (UnsupportedOperationException x) {
-                // test passes, CompletableFutures from withContextCapture are not backed by an executor
-            }
-
             Buffer.set(new StringBuffer("withContextCapture-CompletionStage-test-buffer-E"));
 
             unmanagedStage1.complete(1234);