just use very quick tests

test.py

@@ -232,7 +232,7 @@ def testdcst1D(len, inorm, type, dtype):
     _assert_close(a, pypocketfft.dst(pypocketfft.dst(a, inorm=inorm, type=type), inorm=2-inorm, type=itype), eps)
 
 
-@pmp("len", (3, 4, 1023, 4097))
+@pmp("len", (3, 4, 5, 6, 7, 8, 9, 10))
 @pmp("dtype", dtypes)
 def testfftpack_extra(len, dtype):
     rng = np.random.default_rng(42)