fix(deps): update rust crate indexmap to 2.12.1

Author: nextest-bot

Cargo.lock

@@ -18,7 +18,7 @@ path = "src/bin/generate-junit-corpus.rs"
 
 [dependencies]
 chrono = { version = "0.4.42", default-features = false, features = ["std"] }
-indexmap = "2.11.4"
+indexmap = "2.12.1"
 newtype-uuid = "1.2.4"
 proptest = { version = "1.7.0", optional = true }
 quick-xml = "0.38.4"