m/test/e2e: use concise-style logging

Making our test logs look like LogEntry.ConciseString() means we have
significantly more readable test logs.

Change-Id: I0b1eab6a5a837bb2001f3b32779c23df2feaa381
Reviewed-on: https://review.monogon.dev/c/monogon/+/1362
Reviewed-by: Leopold Schabel <leo@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/test/launch/launch.go b/metropolis/test/launch/launch.go
index e8df009..9760f54 100644
--- a/metropolis/test/launch/launch.go
+++ b/metropolis/test/launch/launch.go
@@ -23,7 +23,6 @@
 	"errors"
 	"fmt"
 	"io"
-	"log"
 	"net"
 	"os"
 	"os/exec"
@@ -67,7 +66,7 @@
 			argsFmt += " "
 		}
 	}
-	log.Printf("Running %s:\n  %s\n", name, argsFmt)
+	Log("Running %s:\n  %s\n", name, argsFmt)
 }
 
 // PortMap represents where VM ports are mapped to on the host. It maps from the VM