The threee tags `<name>`, `</name>` and `<command>` were frequently used
with a leading space that this removes. The reason this habbit is so
widespread in testcases is probably that they have been copy and pasted.
Hence, fixing them all now might curb this practice from now on.
Closes#12028
This leaves the CURLE_RECV_ERROR error code for explicit failure to
receive network data and allows users to better separate the problems.
Ref #8356
Reported-by: Rianov Viacheslav
Closes#8506
