Provide logs from bootstrapping exec into ws pod

[ghost]

If workspace bootstrapping failed due to the fact that the initial exec with curl $binary failed due to connectivity issues of endpoint being malformed, there are no clues in logs. Che server just fails to start a workspace by timeout. The only way to find out what's happening is getting a shell into a workspace pod, and manually curl or wget binaries. This takes time.

There should be command syntax and output from this exec in case it returns failed response code.