tests: increase wfe log level (#7982)

We've been seeing some flaky integration tests where issuance fails. The
integration test only has access to the generic user-facing error. The
real error is available as `InternalError` in the WFE logs, but we need
a higher log level to see it.

test/config-next/wfe2.json

@@ -142,7 +142,7 @@
 		}
 	},
 	"syslog": {
-		"stdoutlevel": 4,
+		"stdoutlevel": 7,
 		"sysloglevel": -1
 	},
 	"openTelemetry": {

test/config/wfe2.json

@@ -141,7 +141,7 @@
 		}
 	},
 	"syslog": {
-		"stdoutlevel": 4,
+		"stdoutlevel": 7,
 		"sysloglevel": 6
 	}
 }