Remove {% jstrans %} tag (#6298)

* Revert {% jstrans %} for .js files

- file extension is enough

* Remove custom jstrans templatetag

* Replace jstrans calls for .html files

- Add "escape=True"

* Allow for custom "escape" argument

* Update custom trans tag

- Cannot pass kwargs in the same way
- Add the "escape" attribute

* Update js translations in html files

ci/check_js_templates.py

@@ -50,7 +50,6 @@ def check_prohibited_tags(data):
         'for',
         'endfor',
         'trans',
-        'jstrans',
         'load',
         'include',
         'url',
@@ -85,7 +84,7 @@ for filename in pathlib.Path(js_dynamic_dir).rglob('*.js'):
     with open(filename, 'r') as js_file:
         data = js_file.readlines()
 
-    invalid_tags = ['trans', 'jstrans']
+    invalid_tags = ['blocktrans', 'blocktranslate', 'trans', 'translate']
 
     err_count = 0