feat: strip custom referencing mechanism from Channel Item

Refs #699

spec/asyncapi.md

@@ -531,7 +531,7 @@ Channels are also known as "topics", "routing keys", "event types" or "paths".
 
 Field Pattern | Type | Description
 ---|:---:|---
-<a name="channelsObjectChannel"></a>{channel} | [Channel Item Object](#channelItemObject) | A relative path to an individual channel. The field name MUST be in the form of a [RFC 6570 URI template](https://tools.ietf.org/html/rfc6570). Query parameters and fragments SHALL NOT be used, instead use [bindings](#channelBindingsObject) to define them.
+<a name="channelsObjectChannel"></a>{channel} | [Channel Item Object](#channelItemObject) \| [Reference Object](#referenceObject) | A relative path to an individual channel. The field name MUST be in the form of a [RFC 6570 URI template](https://tools.ietf.org/html/rfc6570). Query parameters and fragments SHALL NOT be used, instead use [bindings](#channelBindingsObject) to define them.
 
 ##### Channels Object Example
 
@@ -565,7 +565,6 @@ Describes the operations available on a single channel.
 
 Field Name | Type | Description
 ---|:---:|---
-<a name="channelItemObjectRef"></a>$ref | `string` | Allows for an external definition of this channel item. The referenced structure MUST be in the format of a [Channel Item Object](#channelItemObject). If there are conflicts between the referenced definition and this Channel Item's definition, the behavior is *undefined*. <br/><br/>**Deprecated:** Usage of the `$ref` property has been deprecated.
 <a name="channelItemObjectDescription"></a>description | `string` | An optional description of this channel item. [CommonMark syntax](https://spec.commonmark.org/) can be used for rich text representation.
 <a name="channelItemObjectServers"></a>servers | [`string`] | The servers on which this channel is available, specified as an optional unordered list of names (string keys) of [Server Objects](#serverObject) defined in the [Servers Object](#serversObject) (a map). If `servers` is absent or empty then this channel must be available on all servers defined in the [Servers Object](#serversObject).
 <a name="channelItemObjectSubscribe"></a>subscribe | [Operation Object](#operationObject) | A definition of the SUBSCRIBE operation, which defines the messages produced by the application and sent to the channel.
@@ -1439,7 +1438,7 @@ Field Name | Type | Description
 ---|:---|--- 
 <a name="componentsSchemas"></a> schemas | Map[`string`, [Schema Object](#schemaObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Schema Objects](#schemaObject).
 <a name="componentsServers"></a> servers | Map[`string`, [Server Object](#serverObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Server Objects](#serverObject).
-<a name="componentsChannels"></a> channels | Map[`string`, [Channel Item Object](#channelItemObject)] | An object to hold reusable [Channel Item Objects](#channelItemObject).
+<a name="componentsChannels"></a> channels | Map[`string`, [Channel Item Object](#channelItemObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Channel Item Objects](#channelItemObject).
 <a name="componentsMessages"></a> messages | Map[`string`, [Message Object](#messageObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Message Objects](#messageObject).
 <a name="componentsSecuritySchemes"></a> securitySchemes| Map[`string`, [Security Scheme Object](#securitySchemeObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Security Scheme Objects](#securitySchemeObject).
 <a name="componentsParameters"></a> parameters | Map[`string`, [Parameter Object](#parameterObject) \| [Reference Object](#referenceObject)] | An object to hold reusable [Parameter Objects](#parameterObject).