[cantarell-fonts/import-greek-gsoc] Only propagate anchors for composites

[Nikolaus Waxweiler <nwaxweiler src gnome org>]

commit c295538bc53ced4993c7d79f69f6285050717cd2
Author: Nikolaus Waxweiler <madigens gmail com>
Date:   Mon Dec 21 21:43:27 2020 +0000

    Only propagate anchors for composites

 scripts/update-anchor-propagation-includes.py | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/scripts/update-anchor-propagation-includes.py b/scripts/update-anchor-propagation-includes.py
index 66b7cb92..6dea08d9 100644
--- a/scripts/update-anchor-propagation-includes.py
+++ b/scripts/update-anchor-propagation-includes.py
@@ -22,6 +22,9 @@ main_source_path = Path(__file__).parent.parent / "src" / "Cantarell-Regular.ufo
 main_source = ufoLib2.Font.open(main_source_path)
 letters_and_marks = []
 for glyph_name in main_source.glyphOrder:
+    if not main_source[glyph_name].components:
+        continue  # We only care about composites.
+
     if glyph_name.startswith("_"):
         continue