Update docs/upgrade/v1-4-0-to-v1-4-1.md

Co-authored-by: Jillian <[email protected]>

docs/upgrade/v1-4-0-to-v1-4-1.md

@@ -82,11 +82,15 @@ Related issues:
   - [[BUG] v1.4.0 -> v1.4.1-rc1 upgrade stuck in Pre-drained and the node stay in Cordoned](https://github.com/harvester/harvester/issues/7366)
   - [[IMPROVEMENT] Cleanup orphaned volume runtime resources if the resources already deleted](https://github.com/longhorn/longhorn/issues/6764)
 
-### 2. Upgrade with default storage class which is not harvester-longhorn
+### 2. Upgrade with default StorageClass that is not harvester-longhorn
 
-Harvester adds annotation `storageclass.kubernetes.io/is-default-class: "true"` to the `harvester-longhorn` storage class. If user changes the default storage class to another storage class, the harvester ManagedChart shows an error message `cannot patch "harvester-longhorn" with kind StorageClass: admission webhook "validator.harvesterhci.io" denied the request: default storage class %!s(MISSING) already exists, please reset it first`. Also, the webhook deny the upgrade request like following:
+Harvester adds the annotation `storageclass.kubernetes.io/is-default-class: "true"` to `harvester-longhorn`, which is the original default StorageClass. When you replace `harvester-longhorn` with another StorageClass, the following occur:
 
-![Upgrade with another default storage class](/img/v1.4/upgrade/upgrade-with-another-default-storage-class.png)
+- The Harvester ManagedChart shows the error message `cannot patch "harvester-longhorn" with kind StorageClass: admission webhook "validator.harvesterhci.io" denied the request: default storage class %!s(MISSING) already exists, please reset it first`.
+
+- The webhook denies the upgrade request.
+
+    ![Upgrade with another default storage class](/img/v1.4/upgrade/upgrade-with-another-default-storage-class.png)
 
 A few workaround is like following: