Merge pull request #354 from cuviper/release-2.6.0

Release 2.6.0

Author: cuviper

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "indexmap"
 edition = "2021"
-version = "2.5.0"
+version = "2.6.0"
 documentation = "https://docs.rs/indexmap/"
 repository = "https://github.com/indexmap-rs/indexmap"
 license = "Apache-2.0 OR MIT"