[Fix minor typo]Update object-model.mdx (#18590)

## Description 

The owner of a Sui object is 32-byte

docs/content/concepts/object-model.mdx

@@ -15,7 +15,7 @@ Each Sui object has the following metadata:
 - A 32-byte globally unique ID. An object ID is derived from the digest of the transaction that created the object and from a counter encoding the number of IDs generated by the transaction.
 - An 8-byte unsigned integer version that monotonically increases with every transaction that modifies it (see [Object and package versioning](./versioning.mdx)).
 - A 32-byte transaction digest indicating the last transaction that included this object as an output.
-- A 33-byte owner field that indicates how this object can be accessed. See [Object Ownership](./object-ownership.mdx) for more information.
+- A 32-byte owner field that indicates how this object can be accessed. See [Object Ownership](./object-ownership.mdx) for more information.
 
 In addition to common metadata, objects have a category-specific, variable-sized contents field containing a [Binary Canonical Serialization (BCS)](https://docs.rs/bcs/latest/bcs/)-encoded payload.
 
@@ -44,4 +44,4 @@ When this DAG contains all committed transactions in the system, it forms a comp
 
 ## Limits on transactions, objects, and data 
 
-Sui has some limits on transactions and data used in transactions, such as a maximum size and number of objects used. 
+Sui has some limits on transactions and data used in transactions, such as a maximum size and number of objects used.