Update the minimal required Rust version

CHANGELOG.md

@@ -12,6 +12,11 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 
+## [Unreleased]
+
+### Changed
+- The minimal required Rust version is now 1.46.
+
 ## [0.18.0] - 2021-06-13
 
 ### Added

README.md

@@ -79,7 +79,7 @@ man =(curl -sSf "https://raw.githubusercontent.com/breard-r/acmed/main/man/en/ta
 
 ## Build from source
 
-In order to compile ACMEd, you will need the [Rust](https://www.rust-lang.org/) compiler and its package manager, Cargo. The minimal required Rust version is 1.42, although it is recommended to use the latest stable one.
+In order to compile ACMEd, you will need the [Rust](https://www.rust-lang.org/) compiler and its package manager, Cargo. The minimal required Rust version is 1.46, although it is recommended to use the latest stable one.
 
 ACMEd depends OpenSSL 1.1.0 or higher.