Hi from Clara Bee!
The choice of colour really depends on the exact shade and tones of the yellow bricks, and other colours present e.g. in the grout, doors, stained glass, architectural features etc.
This image from Pinterest demonstrates the number of colours in some bricks, and how amazing picking out a complementary colour can be for the window frames, cills etc. If you work around the base colours in the grout or colour flecks in the bricks that is a good start.
Get some tester pots to try inside the porch or on small sections of the cills - the textures of the various materials - render, wood and so on give different intepretations of the colour.
Best wishes
Claire
www.clarabee.com