CI: update test_moderately_small_alpha [wheel build]

The test_moderately_small_alpha dirichlet test fails for 32-bit Windows Python3.13t wheel builds due to a memory error. Decrease the size of the test array by a bit. Note that this test is only run for the mt19937 generator.
numpy · charris · Feb 12, 2025 · Feb 12, 2025 · Feb 12, 2025 · 633874632a26e0af9b225608eff7abec31c92a87
commit 633874632a26e0af9b225608eff7abec31c92a87
diff --git a/numpy/random/tests/test_generator_mt19937.py b/numpy/random/tests/test_generator_mt19937.py
@@ -1244,7 +1244,7 @@ def test_dirichlet_small_alpha(self):
     @pytest.mark.slow
     def test_dirichlet_moderately_small_alpha(self):
         # Use alpha.max() < 0.1 to trigger stick breaking code path
-        alpha = np.array([0.02, 0.04, 0.03])
+        alpha = np.array([0.02, 0.04])
         exact_mean = alpha / alpha.sum()
         random = Generator(MT19937(self.seed))
         sample = random.dirichlet(alpha, size=20000000)