Merge branch 'fix/crt_bundle_unsupported_cert_extension' into 'master'

fix(mbedtls):report an error for certificate files with unsupported extension

See merge request espressif/esp-idf!51518

docs/en/api-reference/protocols/esp_crt_bundle.rst

@@ -30,6 +30,10 @@ Most configuration is done through menuconfig. CMake generates the bundle accord
  * :menuitem:`CONFIG_MBEDTLS_DEFAULT_CERTIFICATE_BUNDLE`: decide which certificates to include from the complete root certificate list.
  * :menuitem:`CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH`: specify the path of any additional certificates to embed in the bundle.
 
+.. note::
+
+    Only PEM encoded certificates with a ``.pem`` extension and DER encoded certificates with a ``.der`` extension are parsed. The extension must match the encoding of the file, for example a PEM encoded certificate saved as ``.crt`` is not accepted. If :ref:`CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH` points directly at a file with any other extension, the build fails; if such a file is found inside a certificate directory, it is skipped and a warning is printed.
+
 To enable the bundle when using ESP-TLS simply pass the function pointer to the bundle attach function:
 
 .. code-block:: c

docs/zh_CN/api-reference/protocols/esp_crt_bundle.rst

@@ -30,6 +30,10 @@ ESP x509 证书包 API 提供了一种简便的方法，帮助你安装自定义
  * :menuitem:`CONFIG_MBEDTLS_DEFAULT_CERTIFICATE_BUNDLE`：决定添加证书列表中的哪些证书。
  * :menuitem:`CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH`：指定要在证书包中嵌入的其他证书的路径。
 
+.. note::
+
+    只有扩展名为 ``.pem`` 的 PEM 编码证书和扩展名为 ``.der`` 的 DER 编码证书会被解析。扩展名必须与文件的编码格式一致，例如保存为 ``.crt`` 的 PEM 编码证书不会被接受。如果 :ref:`CONFIG_MBEDTLS_CUSTOM_CERTIFICATE_BUNDLE_PATH` 直接指向其他扩展名的文件，构建将失败；如果证书目录中存在此类文件，该文件会被跳过并打印警告。
+
 要在使用 ESP-TLS 时启用证书包，将函数指针指向证书包的 attach 函数：
 
 .. code-block:: c