Fix flask backend mimetype for modules (#1131)

* Fix flask backend mimetype for modules

* Update changelog

---------

Co-authored-by: Ryan Morshead <ryan.morshead@gmail.com>

docs/source/about/changelog.rst

@@ -26,6 +26,7 @@ Unreleased
 **Fixed**
 
 - :pull:`1118` - `module_from_template` is broken with a recent release of `requests`
+- :pull:`1131` - `module_from_template` did not work when using Flask backend
 
 
 v1.0.2

src/py/reactpy/reactpy/backend/flask.py

@@ -165,7 +165,7 @@ def _setup_common_routes(
 
     @api_blueprint.route(f"/{MODULES_PATH.name}/<path:path>")
     def send_modules_dir(path: str = "") -> Any:
-        return send_file(safe_web_modules_dir_path(path))
+        return send_file(safe_web_modules_dir_path(path), mimetype="text/javascript")
 
     index_html = read_client_index_html(options)