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
Using the %NOLISTENPORT to trigger a connection failure is somewhat
"risky" (since it isn't guaranteed to not be listened to) and caused
occasional CI problems. This fix changes the infused error to be a more
reliable one but still verifies the --write-out functionality properly -
which is the purpose of this test.
Reported-by: Jay Satiro
Fixes#6621Closes#6623