bump required rust version to 1.81

Author: PSeitz-dd

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tantivy"
-version = "0.24.0"
+version = "0.24.1"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 license = "MIT"
 categories = ["database-implementations", "data-structures"]
@@ -11,7 +11,7 @@ repository = "https://github.com/quickwit-oss/tantivy"
 readme = "README.md"
 keywords = ["search", "information", "retrieval"]
 edition = "2021"
-rust-version = "1.75"
+rust-version = "1.81"
 exclude = ["benches/*.json", "benches/*.txt"]
 
 [dependencies]