fix handling of hardbreak (#2058)

src/textual/widgets/_markdown.py

@@ -639,7 +639,9 @@ class Markdown(Widget):
                     for child in token.children:
                         if child.type == "text":
                             content.append(child.content, style_stack[-1])
-                        if child.type == "softbreak":
+                        elif child.type == "hardbreak":
+                            content.append("\n")
+                        elif child.type == "softbreak":
                             content.append(" ")
                         elif child.type == "code_inline":
                             content.append(