Plugin sync logging improvements (#4963)

# What this PR does
- Fix logging when no error
- Add more logging to request errors during sync"

## Which issue(s) this PR closes

Related to [issue link here]

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## Checklist

- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

grafana-plugin/pkg/plugin/sync.go

@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
+	"io"
 	"net/http"
 	"net/url"
 	"strconv"
@@ -83,7 +84,7 @@ func (a *App) doSync(ctx context.Context, forceSend bool) {
 		var cacheAlreadyLocked *SyncCacheAlreadyLocked
 		if errors.As(err, &cacheAlreadyLocked) {
 			log.DefaultLogger.Info("Skipping sync", "message", err)
-		} else {
+		} else if err != nil {
 			log.DefaultLogger.Error("Error making sync request", "error", err)
 		}
 	}()
@@ -175,6 +176,17 @@ func (a *App) makeSyncRequest(ctx context.Context, forceSend bool) error {
 	}
 	defer res.Body.Close()
 
+	if res.StatusCode != http.StatusOK {
+		bodyBytes, err := io.ReadAll(res.Body)
+		if err != nil {
+			log.DefaultLogger.Error("failed to read response body", "error", err, "status", res.StatusCode)
+		} else {
+			log.DefaultLogger.Error("sync not ok", "status", res.StatusCode, "message", string(bodyBytes))
+		}
+	} else {
+		log.DefaultLogger.Info("sync ok", "status", res.StatusCode)
+	}
+
 	a.lastOnCallSync = onCallSync
 	return nil
 }