[tracker/sam/website-docs-fix] website: Only write 'This is unstable' warning once per file

[Sam Thursfield <sthursfield src gnome org>]

commit 91d9d392a35db0920cc0ab6c496064de5aa5e75e
Author: Sam Thursfield <sam afuera me uk>
Date:   Wed Apr 22 20:10:09 2020 +0200

    website: Only write 'This is unstable' warning once per file

 docs/website/build.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/docs/website/build.py b/docs/website/build.py
index a495d1aa9..6e2c7e2e5 100755
--- a/docs/website/build.py
+++ b/docs/website/build.py
@@ -80,12 +80,15 @@ def add_apidocs_header(text, filename):
         '<div class="section">',
     ]
 
+    wrote_marker = False
+
     with open(filename, encoding='utf8') as f_in:
         with tempfile.NamedTemporaryFile(delete=False, mode='w', encoding='utf8') as f_out:
             for line in f_in:
                 for marker in markers:
-                    if line.find(marker) != -1:
+                    if not wrote_marker and line.find(marker) != -1:
                         f_out.write(text)
+                        wrote_marker = True
                 f_out.write(line)
     shutil.move(f_out.name, filename)