Add array length check when reading port from server.env

Signed-off-by: Kathryn Kodama <kathryn.s.kodama@gmail.com>

src/main/java/io/openliberty/tools/intellij/util/DebugModeHandler.java

@@ -266,7 +266,9 @@ private String readDebugPortFromServerEnv(File serverEnv) throws Exception {
                 }
                 if (lastEntry != null) {
                     String[] parts = lastEntry.split("=");
-                    port = parts[1].trim();
+                    if (parts.length > 1) {
+                        port = parts[1].trim();
+                    }
                 }
             }
         }