Update changelog

CHANGELOG.md

@@ -1,3 +1,9 @@
+### [2.1.12] 2021-11-09
+
+  * Fixed issues in proxied binary files relying on __FILE__ / __DIR__ on php <8 (#10261)
+  * Fixed 9999999-dev being shown in some cases by the `show` command (#10260)
+  * Fixed GitHub Actions output escaping regression on PHP 8.1 (#10250)
+
 ### [2.1.11] 2021-11-02
 
   * Fixed issues in proxied binary files when using declare() on php <8 (#10249)
@@ -1291,6 +1297,7 @@
 
   * Initial release
 
+[2.1.12]: https://github.com/composer/composer/compare/2.1.11...2.1.12
 [2.1.11]: https://github.com/composer/composer/compare/2.1.10...2.1.11
 [2.1.10]: https://github.com/composer/composer/compare/2.1.9...2.1.10
 [2.1.9]: https://github.com/composer/composer/compare/2.1.8...2.1.9