Fix AbortPolicyWithReportTest as con could be used as a directory name in Windows server 2025 (#15672)

Author: zrlw

dubbo-common/src/test/java/org/apache/dubbo/common/threadpool/support/AbortPolicyWithReportTest.java

@@ -156,9 +156,9 @@ private String dumpDirectoryCannotBeCreated() {
         final String os =
                 SystemPropertyConfigUtils.getSystemProperty(SYSTEM_OS_NAME).toLowerCase();
         if (os.contains(OS_WIN_PREFIX)) {
-            // "con" is one of Windows reserved names,
+            // colon is a reserved character which could not be used in a file or directory name,
             // https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file
-            return "con";
+            return "c:o:n";
         } else {
             return "/dev/full/" + UUID.randomUUID().toString();
         }