chore: add tips for encoding errors

README.md

@@ -41,6 +41,22 @@ git submodule update --init --recursive
 make run
 ```
 
+If you encounter some errors like:
+
+```
+app/_plugins/generators/utils/frontmatter_parser.rb:8:in `match': invalid byte sequence in US-ASCII (ArgumentError)
+
+      @result = @string.match(Jekyll::Document::YAML_FRONT_MATTER_REGEXP)
+                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+    from app/_plugins/generators/utils/frontmatter_parser.rb:8:in `match'
+```
+
+You can try setting the `LANG` or `LC_ALL` environment variable to `en_US.UTF-8`. For example:
+
+```bash
+export LANG=en_US.UTF-8
+```
+
 ### OAS Pages
 
 Create local .env file