Bug 561967 - [Tests] 3 tests failing on cen64-gtk3 since I20200406-0350

Change-Id: I3af79faa61503b0d2a416da6b2054b96e039d95d
diff --git a/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/core/ProcessTests.java b/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/core/ProcessTests.java
index 949830c..bb8a361 100644
--- a/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/core/ProcessTests.java
+++ b/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/core/ProcessTests.java
@@ -14,6 +14,7 @@
 package org.eclipse.jdt.debug.tests.core;
 
 import java.io.File;
+import java.io.OutputStream;
 
 import org.eclipse.core.runtime.Platform;
 import org.eclipse.debug.core.DebugException;
@@ -71,8 +72,10 @@
 		if (Platform.getOS().equals(Platform.OS_LINUX)) {
 			// printing env command
 			{
-				Runtime.getRuntime().exec("env");
+				Process p = Runtime.getRuntime().exec("env");
+				OutputStream processOut = p.getOutputStream();
 				Thread.sleep(500);
+				processOut.flush();
 
 			}
 			process = DebugPlugin.exec(new String[] { "java" }, new File("/tmp"));