Prepare string-interner v0.20 (#105)

* add changelog for v0.20

* bump crate version

Author: Robbepop

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "string-interner"
-version = "0.19.0"
+version = "0.20.0"
 authors = ["Robbepop"]
 license = "MIT/Apache-2.0"
 readme = "README.md"

Cargo.toml

@@ -1,5 +1,25 @@
 # Release Notes
 
+## 0.20.0 - 2026/04/30
+
+### Fixed
+
+- Fixed off-by-one bug in `serde` support. [#91]
+
+### Improvements
+
+- Improve documentation about custom hashing. [#90]
+- Add notification about `unchecked` resolution for `BufferBackend`. [#92]
+- Updated dependencies. [#100] [#101]
+- Specify Rust MSRV to be 1.65. [#101]
+
+[#90]: https://github.com/Robbepop/string-interner/pull/90
+[#91]: https://github.com/Robbepop/string-interner/pull/91
+[#92]: https://github.com/Robbepop/string-interner/pull/92
+[#96]: https://github.com/Robbepop/string-interner/pull/96
+[#100]: https://github.com/Robbepop/string-interner/pull/100
+[#101]: https://github.com/Robbepop/string-interner/pull/101
+
 ## 0.19.0 - 2025/02/11
 
 ## Fixed