Fixes a typo in arrow/examples/README.md (#7473)

Author: Mottl

arrow/examples/README.md

@@ -24,6 +24,6 @@
 - [`dynamic_types.rs`](dynamic_types.rs): Dealing with mixed types dynamically at runtime
 - [`read_csv.rs`](read_csv.rs): Reading CSV files with explicit schema, pretty printing Arrays
 - [`read_csv_infer_schema.rs`](read_csv_infer_schema.rs): Reading CSV files, pretty printing Arrays
-- [`zero_copy_ipc`](zero_copy_ipc): Zero copy read of Arrow IPC file using `mmap`
+- [`zero_copy_ipc.rs`](zero_copy_ipc.rs): Zero copy read of Arrow IPC file using `mmap`
 - [`tensor_builder.rs`](tensor_builder.rs): Using tensor builder
 - [`version.rs`](version.rs): Print the arrow version and exit