chore: add .md extension to .editorconfig

Author: hegemonic

Diff for: .editorconfig

@@ -3,6 +3,6 @@ charset = utf-8
 insert_final_newline = true
 trim_trailing_whitespace = true
 
-[{**/*.cjs, **/*.css,**/*.js,*.json,**/*.less,**/*.mjs,**/*.njk,**/*.scss,**/*.yaml}]
+[{**/*.cjs, **/*.css,**/*.js,*.json,**/*.less,**/*.md,**/*.mjs,**/*.njk,**/*.scss,**/*.yaml}]
 indent_style = space
 indent_size = 2