Merge pull request #910 from Mark-Simulacrum/1.57-dev-release

Adds pre-release testing call

Author: pietroalbini

posts/inside-rust/2021-11-30-1.57.0-prerelease.md

@@ -0,0 +1,21 @@
+---
+layout: post
+title: "1.57.0 pre-release testing"
+author: Mark Rousskov
+team: The Release Team <https://www.rust-lang.org/governance/teams/release>
+---
+
+The 1.57.0 pre-release is ready for testing. The release is scheduled for this
+Thursday, December 2nd. [Release notes can be found here.][relnotes]
+
+You can try it out locally by running:
+
+```plain
+RUSTUP_DIST_SERVER=https://dev-static.rust-lang.org rustup update stable
+```
+
+The index is <https://dev-static.rust-lang.org/dist/2021-11-30/index.html>. You
+can leave feedback on the [internals thread][internals].
+
+[relnotes]: https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1570-2021-12-02
+[internals]: https://internals.rust-lang.org/t/rust-1-57-0-prerelease-testing/15690