docs: make table.update() nodejs guide consistent with API documentation (#2334)

The docs in the Guide here do not match the [API reference]
(https://lancedb.github.io/lancedb/js/classes/Table/#updateopts) for the
nodejs client.

I am writing an Elixir wrapper over the typescript library (Rust
forthcoming!) and confirmed in testing that the API reference is correct
vs the Guide.

Following the Guide docs, the error I got was:

"lance error: Invalid user input: Schema error: No field named bar.
Valid fields are foo. For a query of:

await table.update({foo: "buzz"}, { where: "foo = 'bar'"});
Over a table with a schema of just {foo: Utf8}.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- **Documentation**
- Reformatted a code snippet in the guide to enhance readability by
splitting it into multiple lines for improved clarity.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

docs/src/guides/tables.md

@@ -765,7 +765,10 @@ This can be used to update zero to all rows depending on how many rows match the
         ];
         const tbl = await db.createTable("my_table", data)
 
-        await tbl.update({vector: [10, 10]}, { where: "x = 2"})
+        await tbl.update({ 
+            values: { vector: [10, 10] },
+            where: "x = 2"
+        });
         ```
 
     === "vectordb (deprecated)"
@@ -784,7 +787,10 @@ This can be used to update zero to all rows depending on how many rows match the
         ];
         const tbl = await db.createTable("my_table", data)
 
-        await tbl.update({ where: "x = 2", values: {vector: [10, 10]} })
+        await tbl.update({ 
+            where: "x = 2", 
+            values: { vector: [10, 10] } 
+        });
         ```
 
 #### Updating using a sql query