Remove the deprecated/unused mdbook 'multilingual' setting

sourcefrog · sourcefrog · commit 2fcb00b113c8 · 2025-12-07T19:37:31.000-08:00
diff --git a/book/book.toml b/book/book.toml
@@ -1,7 +1,6 @@
 [book]
 authors = ["Martin Pool"]
 language = "en"
-multilingual = false
 src = "src"
 title = "cargo-mutants"
 
