Add top line to towncrier template

The-Compiler · The-Compiler · commit 265397840373 · 2021-08-27T14:51:10.000+02:00
Fixes pytest-dev#8817 Supersedes pytest-dev#9045 See twisted/towncrier#346 and twisted/towncrier#340
diff --git a/changelog/_template.rst b/changelog/_template.rst
@@ -1,3 +1,6 @@
+
+{{ top_underline * ((top_line)|length)}}
+
 {% for section in sections %}
 {% set underline = "-" %}
 {% if section %}
