docs: remove description for xtaggroup when using join command (#1422)

* docs: update join command docs related to x-taggroups changes

Co-authored-by: Andrew Tatomyr <[email protected]>

---------

Co-authored-by: Andrew Tatomyr <[email protected]>

docs/commands/join.md

@@ -94,26 +94,26 @@ externalDocs
 
 By default, the `info.description` property is taken only from the first file, even if it exists in other input files.
 
-However, if any of the input files contain the `tags` object, the `join` command automatically creates the `x-tagGroups` object in the output file. This object contains the `info.description` property from each of the input files.
+However, if any of the input files contain the `tags` object, the `join` command automatically creates the `x-tagGroups` object in the output file.
 
 ```yaml
 x-tagGroups:
   - name: first-api
     tags:
       - expanded
       - other
-    description: 'Text from info: description of the first input file'
   - name: second-api
     tags:
       - partner
-    description: 'Text from info: description of the second input file'
 ```
 
 {% admonition type="info" %}
 If some operations in an input file don't have a tag assigned to them, the `join` command automatically adds the `other` tag to those operations in the output file. The `other` tag is also included in the `x-tagGroups` object.
 
 If any of the input files contain the `x-tagGroups` object, the content of this object is ignored by the `join` command and not included in the output file.
 
+The `info.title` field is used as a name in `x-tagGroups` instead of a file name for the `join` command, so you can join files with the same names. If you need to adjust the `info.title` field, you can also use the [info-override decorator](https://redocly.com/docs/cli/decorators/info-override/).
+
 {% /admonition %}
 
 The `servers` object combines the content from all input files, starting with the content from the first file. Commented lines are not included in the output file.