[T/NL] Increase tolerance of extrapolation test.

Tests/NumLib/TestExtrapolation.cpp

@@ -219,7 +219,7 @@ void extrapolate(ExtrapolationTestProcess const& pcs,
 {
     namespace LinAlg = MathLib::LinAlg;
 
-    auto const tolerance_dx = 30.0 * std::numeric_limits<double>::epsilon();
+    auto const tolerance_dx = 31.0 * std::numeric_limits<double>::epsilon();
     auto const tolerance_res = 15.0 * std::numeric_limits<double>::epsilon();
 
     const double t = 0.0;