Workaround the effects of global warming in ARM benchmarks. (#185)
Workaround the effects of global warming in ARM benchmarks. (#185)

Summer is here, and with it an increased room temperature when
benchmarking JPEG XL on the ARM board, making it never reach the
internal CPU temp threshold to start the test. This workarounds the
issue by limiting the temperature waiting time to 5 seconds and
increasing the threshold to 38 C.

Tested with:
```
echo 42000 > fake_temp
THERMAL_FILE=fake_temp SKIP_CPUSET=1 ./ci.sh arm_benchmark
```
libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl