Apply ruff/refurb rule FURB129

FURB129 Instead of calling `readlines()`, iterate over file object directly

Author: DimitriPapadopoulos

testing/cffi1/test_commontypes.py

@@ -9,7 +9,7 @@ def getlines():
                               '..', 'c', 'commontypes.c'))
     except OSError:
         pytest.skip("cannot find ../c/commontypes.c")
-    lines = [line for line in f.readlines() if line.strip().startswith('EQ(')]
+    lines = [line for line in f if line.strip().startswith('EQ(')]
     f.close()
     return lines