raise msrv to 1.75

Author: audunhalland

Cargo.toml

@@ -17,7 +17,7 @@ license = "MPL-2.0"
 readme = "README.md"
 repository = "https://github.com/rust-lang/mdBook"
 description = "Creates a book from markdown files"
-rust-version = "1.74"
+rust-version = "1.75"
 
 [dependencies]
 anyhow = "1.0.71"