Added docs for 0.40.0

Author: mbrandonw

README.md

@@ -390,12 +390,13 @@ You can add ComposableArchitecture to an Xcode project by adding it as a package
 The documentation for releases and `main` are available here:
 
 * [`main`](https://pointfreeco.github.io/swift-composable-architecture/main/documentation/composablearchitecture)
-* [0.39.0](https://pointfreeco.github.io/swift-composable-architecture/0.39.0/documentation/composablearchitecture/)
+* [0.40.0](https://pointfreeco.github.io/swift-composable-architecture/0.40.0/documentation/composablearchitecture/)
 <details>
   <summary>
   Other versions
   </summary>
 
+  * [0.39.0](https://pointfreeco.github.io/swift-composable-architecture/0.39.0/documentation/composablearchitecture/)
   * [0.38.0](https://pointfreeco.github.io/swift-composable-architecture/0.38.0/documentation/composablearchitecture/)
   * [0.37.0](https://pointfreeco.github.io/swift-composable-architecture/0.37.0/documentation/composablearchitecture)
   * [0.36.0](https://pointfreeco.github.io/swift-composable-architecture/0.36.0/documentation/composablearchitecture)