Add custom-amsthm-environments Quarto extension

(cherry picked from commit 8151bff)

Author: MateusMolina

docs/extensions/listings/shortcodes-and-filters.yml

@@ -682,3 +682,9 @@
   path: https://github.com/andrewheiss/quarto-wordcount
   author: '[Andrew Heiss](https://github.com/andrewheiss/)'
   description: Quarto extension for calculating accurate word counts
+
+- name: custom-amsthm-environments
+  path: https://github.com/MateusMolina/custom-amsthm-environments
+  author: '[Mateus Molina](https://github.com/MateusMolina/)'
+  description: Quarto extension for defining custom theorem-like environments.
+