Update release to 2.3.1

Includes a contribution by @russellbanks which changes windows to use the windows-sys crate instead of winapi, as suggested by @thewh1teagle.

Specifies a rust version of 1.68, which is the one that was current when this major version was released.  Only the library is warranted to build on 1.68.

Cargo.toml

@@ -6,7 +6,8 @@ keywords = ["password", "credential", "keychain", "keyring", "cross-platform"]
 license = "MIT OR Apache-2.0"
 name = "keyring"
 repository = "https://github.com/hwchen/keyring-rs.git"
-version = "2.3.0"
+version = "2.3.1"
+rust-version = "1.68"
 edition = "2021"
 exclude = [".github/"]
 readme = "README.md"

README.md

@@ -122,6 +122,12 @@ unintended and undefined (suppressing default features did nothing),
 so this is considered a bug fix rather than
 a semver-breaking change that requires a major version bump.
 
+ALSO NOTE: Although the TOML file for this crate specifies a minimum
+Rust version of 1.68, that version apples to the library builds _only_.
+The TOML has development dependencies that require Rust 1.70.  We
+keep each major version of the library compiling on Rust versions 
+that are at least as old as the initial release of that major version.
+
 ## Upgrading from v1
 
 The v2 release,
@@ -179,12 +185,14 @@ whether through contributing code, discussion, or bug reports!
 - @Phrohdoh
 - @phlip9
 - @Rukenshia
+- @russellbanks
 - @ryanavella
 - @samuela
 - @stankec
 - @steveatinfincia
 - @Sytten
 - @VorpalBlade
+- @thewh1teagle
 
 If you should be on this list, but don't find yourself, 
 please contact @brotskydotcom.

build-xplat-binaries.sh

@@ -1,5 +1,10 @@
 #!/bin/bash
 echo Rustup and Cargo updates...
+rustup install 1.68
+rustup +1.68 target add aarch64-unknown-linux-musl
+rustup +1.68 target add aarch64-pc-windows-msvc
+rustup +1.68 target add aarch64-apple-darwin
+rustup +1.68 target add aarch64-apple-ios
 rustup update
 cargo update
 echo Clippy no default features...
@@ -22,3 +27,8 @@ cargo build --target aarch64-unknown-linux-musl
 cargo build --target aarch64-pc-windows-msvc
 cargo build --target aarch64-apple-darwin
 cargo build --target aarch64-apple-ios
+echo Compile library on 1.68
+cargo +1.68 build --target aarch64-unknown-linux-musl --lib
+cargo +1.68 build --target aarch64-pc-windows-msvc --lib
+cargo +1.68 build --target aarch64-apple-darwin --lib
+cargo +1.68 build --target aarch64-apple-ios --lib