修正office.preview.switch.disabled引用了错误常量的问题

server/src/main/java/cn/keking/config/ConfigRefreshComponent.java

@@ -57,7 +57,7 @@ public class ConfigRefreshComponent {
                     text = properties.getProperty("simText", ConfigConstants.DEFAULT_TXT_TYPE);
                     media = properties.getProperty("media", ConfigConstants.DEFAULT_MEDIA_TYPE);
                     officePreviewType = properties.getProperty("office.preview.type", ConfigConstants.DEFAULT_OFFICE_PREVIEW_TYPE);
-                    officePreviewSwitchDisabled = properties.getProperty("office.preview.switch.disabled", ConfigConstants.DEFAULT_OFFICE_PREVIEW_TYPE);
+                    officePreviewSwitchDisabled = properties.getProperty("office.preview.switch.disabled", ConfigConstants.DEFAULT_OFFICE_PREVIEW_SWITCH_DISABLED);
                     ftpUsername = properties.getProperty("ftp.username", ConfigConstants.DEFAULT_FTP_USERNAME);
                     ftpPassword = properties.getProperty("ftp.password", ConfigConstants.DEFAULT_FTP_PASSWORD);
                     ftpControlEncoding = properties.getProperty("ftp.control.encoding", ConfigConstants.DEFAULT_FTP_CONTROL_ENCODING);