fix: Rust doc fix (#1113)

## Which issue does this PR close?

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- Closes #1112 .

## What changes are included in this PR?
Added back original Anchor tags

Author: jonathanc-n

crates/examples/src/rest_catalog_namespace.rs

@@ -31,19 +31,24 @@ static REST_URI: &str = "http://localhost:8181";
 /// [quickstart documentation](https://iceberg.apache.org/spark-quickstart/).
 #[tokio::main]
 async fn main() {
+    // ANCHOR: create_catalog
     // Create the REST iceberg catalog.
     let config = RestCatalogConfig::builder()
         .uri(REST_URI.to_string())
         .build();
     let catalog = RestCatalog::new(config);
+    // ANCHOR_END: create_catalog
 
+    // ANCHOR: list_all_namespace
     // List all namespaces already in the catalog.
     let existing_namespaces = catalog.list_namespaces(None).await.unwrap();
     println!(
         "Namespaces alreading in the existing catalog: {:?}",
         existing_namespaces
     );
+    // ANCHOR_END: list_all_namespace
 
+    // ANCHOR: create_namespace
     // Create a new namespace identifier.
     let namespace_ident =
         NamespaceIdent::from_vec(vec!["ns1".to_string(), "ns11".to_string()]).unwrap();
@@ -66,4 +71,5 @@ async fn main() {
 
     let loaded_namespace = catalog.get_namespace(&namespace_ident).await.unwrap();
     println!("Namespace loaded!\n\nNamespace: {:#?}", loaded_namespace,);
+    // ANCHOR_END: create_namespace
 }

crates/examples/src/rest_catalog_table.rs

@@ -40,6 +40,7 @@ async fn main() {
         .build();
     let catalog = RestCatalog::new(config);
 
+    // ANCHOR: create_table
     // Create the table identifier.
     let namespace_ident = NamespaceIdent::from_vec(vec![NAMESPACE.to_string()]).unwrap();
     let table_ident = TableIdent::new(namespace_ident.clone(), TABLE_NAME.to_string());
@@ -78,7 +79,9 @@ async fn main() {
         .await
         .unwrap();
     println!("Table {TABLE_NAME} created!");
+    // ANCHOR_END: create_table
 
+    // ANCHOR: load_table
     // Ensure that the table is under the correct namespace.
     assert!(catalog
         .list_tables(&namespace_ident)
@@ -89,4 +92,5 @@ async fn main() {
     // Load the table back from the catalog. It should be identical to the created table.
     let loaded_table = catalog.load_table(&table_ident).await.unwrap();
     println!("Table {TABLE_NAME} loaded!\n\nTable: {:?}", loaded_table);
+    // ANCHOR_END: load_table
 }