Update explanation of how to generate imutable files

Author: sfauvel

mithril-test-lab/test_data/README.md

@@ -5,69 +5,5 @@
 > immutable db directory by our db parser (see ([immutable_file.rs](./../../mithril-common/src/digesters/immutable_file.rs))).
 
 > [!NOTE]
-> The `.primary` and `.secondary` files are not real data. They're empty files that are
-> here in order to simulate a real cardano immutable db structure.
-
-These files were generated manually from the blocks in the sibling folder:
-
-| Imput Block file | Number of transactions | Output immutable file |
-|------------------|------------------------|-----------------------|
-| [byron2.block](./blocks/byron2.block) | `2` | `00000.chunk`         |
-| [shelley1.block](./blocks/shelley1.block) | `4` | `00000.chunk`         |
-| [mary1.block](./blocks/mary1.block) | `14` | `00000.chunk`         |
-| [allegra1.block](./blocks/allegra1.block) | `3` | `00001.chunk`         |
-| [alonzo1.block](./blocks/alonzo1.block) | `5` | `00001.chunk`         |
-| [conway1.block](./blocks/conway1.block) | `1` | `00001.chunk`         |
-
-The following code was used to generate the immutable files:
-```rust
-use std::io::Write;
-
-let immutable_files = vec![
-    (
-        "./00000.chunk",
-        vec![
-            (
-                include_str!("./blocks/byron2.block"),
-                2usize,
-            ),
-            (
-                include_str!("./blocks/shelley1.block"),
-                4,
-            ),
-            (
-                include_str!("./blocks/mary1.block"),
-                14,
-            ),
-        ],
-    ),
-    (
-        "./00001.chunk",
-        vec![
-            (
-                include_str!("./blocks/allegra1.block"),
-                3,
-            ),
-            (
-                include_str!("./blocks/alonzo1.block"),
-                5,
-            ),
-            (
-                include_str!("./blocks/conway1.block"),
-                5,
-            ),
-        ],
-    ),
-];
-
-for immutable_file_definition in immutable_files {
-    let immutable_file_path = immutable_file_definition.0;
-    let mut immutable_file = fs::File::create(immutable_file_path).unwrap();
-
-    for (block_str, _tx_count) in immutable_file_definition.1.into_iter() {
-        let cbor = hex::decode(block_str).expect("invalid hex");
-        immutable_file.write_all(&cbor).unwrap();
-    }
-}
-```
-
+> The immutable files (`.chunk`, `.primary` and `.secondary`) files are data that are the result of
+> the `mithril-end-to-end` test command execution.