increase tolerance for the PipeCg::ApplyIsEquivalentToRef test

Author: gojakuch

test/solver/pipe_cg_kernels.cpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2025 The Ginkgo authors
+// SPDX-FileCopyrightText: 2025 - 2026 The Ginkgo authors
 //
 // SPDX-License-Identifier: BSD-3-Clause
 
@@ -246,5 +246,5 @@ TEST_F(PipeCg, ApplyIsEquivalentToRef)
     solver->apply(b, x);
     d_solver->apply(d_b, d_x);
 
-    GKO_ASSERT_MTX_NEAR(d_x, x, ::r<value_type>::value * 5 * 1e4);
+    GKO_ASSERT_MTX_NEAR(d_x, x, ::r<value_type>::value * 6 * 1e4);
 }