SpeedTest reports negative number

[RobWalker]

Describe the bug

The speed test dashboard shows a worst speed of -133MB/s ... which is interesting?!

This logs like it might correlate with error logs:

speedtest_exporter_1 | time="2021-10-01T11:52:37Z" level=error msg="failed to carry out upload test: Post "http://speedtest.tor.fibrestream.ca:8080/speedtest/upload.php\": write tcp 172.18.0.2:51928->162.250.172.153:8080: use of closed network connection"

speedtest_exporter_1 | time="2021-10-01T16:53:27Z" level=error msg="failed to carry out upload test: Post "http://speedtest.us-east-02.greenhousedata.com:8080/speedtest/upload.php\": EOF"

Expected behavior

Failed speed tests should probably just be ignored from a stats perspective?

Additional context

Windows host, running latest image.