Fix test timeout when body.Read() returns error other than io.EOF
Fix test timeout when body.Read() returns error other than io.EOF

If the read at line 901 returned an error other than `io.EOF`, the
surrounding loop would continue in infinity. This commit ensures that
the loop brakes on any error.

Signed-off-by: Thomas Hallgren <5f50a84c1fa3bcff146405017f36aec1a10a9e38@datawire.io>

datawire/telepresence,datawire/telepresence,datawire/telepresence