docs: add mrr tests for weekly execution in 2n-aws and 3n-aws - Tests: ip4base, ip4scale2m, l2xc. - Core,threads: 1c2t, 2c4t. - Frame sizes: 64B, 1518B. Change-Id: Ic1f1eac21780c834ad67457aa9721b82ad837785 Signed-off-by: Maciek Konstantynowicz <mkonstan@cisco.com>