chore: update README.md to mention about include_str

Author: yamgent

README.md

@@ -2,5 +2,6 @@
 
 1. Clone template
 2. Replace all `xxxx` with current year (do not accidentally replace content inside `actual_inputs` folder!)
-3. Add `INPUT_REPO_TOKEN` secret with access to `actual_inputs` folder so that CI can access the inputs
+3. Update the `src/bin/empty/main.rs` `include_str!()` macro to use the correct year.
+4. Add `INPUT_REPO_TOKEN` secret with access to `actual_inputs` folder so that CI can access the inputs
     * Just "Contents - Read-only" access for the input repo is sufficient

src/bin/empty/main.rs

@@ -1,4 +1,4 @@
-const ACTUAL_INPUT: &str = include_str!("../../../actual_inputs/2023/01/input.txt");
+const ACTUAL_INPUT: &str = include_str!("../../../actual_inputs/2015/01/input.txt");
 
 fn p1(input: &str) -> String {
     let _input = input.trim();