[Durable Objects] Remove stray back tick in alarms.mdx (#21653)

Author: canac

src/content/docs/durable-objects/api/alarms.mdx

@@ -56,7 +56,7 @@ Alarms can be used to build distributed primitives, like queues or batching of w
 
 ### `alarm`
 
-- <code>alarm(`alarmInfo`<Type text="Object"/>)</code>`: <Type text='void' />
+- <code>alarm(`alarmInfo`<Type text="Object"/>)</code>: <Type text='void' />
 
   - Called by the system when a scheduled alarm time is reached.