Allow gettext test to skip on macOS.

run_project_tests.py

diff --git a/run_project_tests.py b/run_project_tests.py
index ba42681..aa259db 100755
--- a/run_project_tests.py
+++ b/run_project_tests.py
@@ -962,6 +962,9 @@
     if not t.category.endswith('frameworks'):
         return True
 
+    if '6 gettext' in t.path and mesonlib.is_osx():
+        return True
+
     return False
 
 def skip_csharp(backend: Backend) -> bool: