debugResult logs on StdErr

[HenrikLindholm86]

Describe the bug
The debugResult function in debug.go is logging everything on StdErr instead of StdOut

DebugResult function where it logs on stdErr at the end

func debugResult(log *logrus.Logger, m interface{}) {
	if !log.IsLevelEnabled(logrus.DebugLevel) {
		return
	}

	debugStr, err := json.MarshalIndent(m, "", "  ")
	if err != nil {
		log.Errorf("cannot marshal struct for debug: %s", err)
		return
	}

	// don't use logrus because:
	// 1. It will escape new lines and " making it harder to read and to use
	// 2. It will add timestamp
	// 3. This way is easier to copy/paste to put the info in a ticket
	fmt.Fprintln(os.Stderr, string(debugStr))
}

To Reproduce
Start the mongodb_exporter with log level debug
arguments we use when starting
--discovering-mode --compatible-mode --collect-all --log.level=debug

Expected behavior
Output from debugResult should not be logged as error.

Logs
Short snippet of the error logs

ERROR 2023-12-28T09:26:21.695767244Z time="2023-12-28T09:26:21Z" level=debug msg="getDiagnosticData result"
ERROR 2023-12-28T09:26:21.701590367Z {
ERROR 2023-12-28T09:26:21.701639965Z "end": "2023-12-28T09:26:21.002Z",
ERROR 2023-12-28T09:26:21.701646738Z "local.oplog.rs.stats": {
ERROR 2023-12-28T09:26:21.701651498Z "avgObjSize": 258,
ERROR 2023-12-28T09:26:21.701654887Z "capped": true,
ERROR 2023-12-28T09:26:21.701658424Z "count": 3971664,
ERROR 2023-12-28T09:26:21.701662125Z "end": "2023-12-28T09:26:21.001Z",
ERROR 2023-12-28T09:26:21.701666504Z "freeStorageSize": 17514496,
ERROR 2023-12-28T09:26:21.701670379Z "indexBuilds": [],
ERROR 2023-12-28T09:26:21.701674233Z "indexDetails": {},
ERROR 2023-12-28T09:26:21.701677888Z "indexSizes": {},
ERROR 2023-12-28T09:26:21.701681546Z "max": 0,
ERROR 2023-12-28T09:26:21.701685056Z "maxSize": 1038090240,
ERROR 2023-12-28T09:26:21.701688572Z "nindexes": 0,
ERROR 2023-12-28T09:26:21.701692286Z "ns": "local.oplog.rs",
ERROR 2023-12-28T09:26:21.701696076Z "numOrphanDocs": 0,
ERROR 2023-12-28T09:26:21.701699915Z "ok": 1,
ERROR 2023-12-28T09:26:21.701703615Z "scaleFactor": 1,
ERROR 2023-12-28T09:26:21.701707311Z "size": 1026440689,
ERROR 2023-12-28T09:26:21.701710843Z "start": "2023-12-28T09:26:21.001Z",
ERROR 2023-12-28T09:26:21.701714213Z "storageSize": 197496832,
ERROR 2023-12-28T09:26:21.701717622Z "totalIndexSize": 0,
ERROR 2023-12-28T09:26:21.701721117Z "totalSize": 197496832,
ERROR 2023-12-28T09:26:21.701724374Z "wiredTiger": {
ERROR 2023-12-28T09:26:21.701727809Z "LSM": {
ERROR 2023-12-28T09:26:21.701731704Z "bloom filter false positives": 0,
ERROR 2023-12-28T09:26:21.701735149Z "bloom filter hits": 0,
ERROR 2023-12-28T09:26:21.701738687Z "bloom filter misses": 0,
ERROR 2023-12-28T09:26:21.701743431Z "bloom filter pages evicted from cache": 0,
ERROR 2023-12-28T09:26:21.701746844Z "bloom filter pages read into cache": 0,
ERROR 2023-12-28T09:26:21.701755641Z "bloom filters in the LSM tree": 0,
ERROR 2023-12-28T09:26:21.701759143Z "chunks in the LSM tree": 0,
ERROR 2023-12-28T09:26:21.701778657Z "highest merge generation in the LSM tree": 0,
ERROR 2023-12-28T09:26:21.701783163Z "queries that could have benefited from a Bloom filter that did not exist": 0,
ERROR 2023-12-28T09:26:21.701786658Z "sleep for LSM checkpoint throttle": 0,
ERROR 2023-12-28T09:26:21.701790175Z "sleep for LSM merge throttle": 0,
ERROR 2023-12-28T09:26:21.701793741Z "total size of bloom filters": 0
ERROR 2023-12-28T09:26:21.701797100Z },
ERROR 2023-12-28T09:26:21.701800637Z "block-manager": {
... etc

Environment

• k8s in GCP,
• mongodb_exporter image = percona/mongodb_exporter:0.39
• percona server mongodb image = percona/percona-server-mongodb:6.0.4-3