69260 Increase device run perf test timeout (cla: yes, team)

69266 Decrease device discovery timeout from 10 to 5 seconds (cla: yes, team)

69268 [devicelab] do not fail test if CPU measurement is not recorded (cla: yes, team)

69272 [devicelab] retry startup of start up test (cla: yes, team)

69273 [devicelab] work around occasional null values for devtools (cla: yes, team)

69338 Mark flutter_gallery_sksl_warmup__transition_perf_e2e_ios32 as unflaky (cla: yes, team)

69339 Do not fail if average_memory_usage is not recorded (cla: yes, team, team: flakes)