Bump MSRV to 1.53 (#731)

.github/workflows/test.yml

@@ -81,8 +81,8 @@ jobs:
             rust: stable
           - name: beta
             rust: beta
-          - name: 1.52.1
-            rust: 1.52.1
+          - name: 1.53.0
+            rust: 1.53.0
 
     steps:
       - name: Checkout

CHANGELOG.md

@@ -5,7 +5,7 @@
 
 Several breaking changes were made between 0.9 and 0.10, but changes should be straightforward:
 
-* MSRV is now 1.52.1
+* MSRV is now 1.53.0
 * The `lettre_email` crate has been merged into `lettre`. To migrate, replace `lettre_email` with `lettre::message`
   and make sure to enable the `builder` feature (it's enabled by default).
 * `SendableEmail` has been renamed to `Email` and `EmailBuilder::build()` produces it directly. To migrate,

README.md

@@ -65,7 +65,7 @@ Lettre does not provide (for now):
 
 ## Example
 
-This library requires Rust 1.52.1 or newer.
+This library requires Rust 1.53.0 or newer.
 To use this library, add the following to your `Cargo.toml`: