message: Minor random lmat usage in the tests.
diff: @@ -81,6 +81,14 @@ protected:
  std::normal_distribution<>(-1.0, 1.0), rand_engine, ref);
  }
  + std::unique_ptr<Mtx> gen_l_mtx(int num_rows, int num_cols)
  + {
  + return gko::test::generate_random_matrix<Mtx>(
  + num_rows, num_cols,
  + std::uniform_int_distribution<>(num_cols, num_cols),
  + std::normal_distribution<>(-1.0, 1.0), rand_engine, ref);
  + }
  +
  std::shared_ptr<gko::ReferenceExecutor> ref;
  std::shared_ptr<const gko::CudaExecutor> cuda;
  @@ -90,7 +98,7 @@ protected:
  TEST_F(LowerTrs, CudaApplyIsEquivalentToRef)
  {
  - std::shared_ptr<Mtx> mtx = gen_mtx(50, 50);
  + std::shared_ptr<Mtx> mtx = gen_l_mtx(50, 50);
  std::shared_ptr<Mtx> b = gen_mtx(50, 1);
  std::shared_ptr<Mtx> x = gen_mtx(50, 1);
  std::shared_ptr<CsrMtx> csr_mtx = CsrMtx::create(ref);
  