Replace io/ioutils as it is deprecated (#45)

cmd/datasetIngestor/main.go

@@ -42,7 +42,6 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
@@ -217,7 +216,7 @@ func main() {
 		folders = append(folders, sourceFolder)
 	} else {
 		// get folders from file
-		folderlist, err := ioutil.ReadFile(folderlistingPath)
+		folderlist, err := os.ReadFile(folderlistingPath)
 		if err != nil {
 			log.Fatal(err)
 		}

datasetIngestor/checkMetadata.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"github.com/paulscherrerinstitute/scicat/datasetUtils"
-	"io/ioutil"
+	"io"
 	"log"
 	"net"
 	"net/http"
@@ -61,7 +61,7 @@ func CheckMetadata(client *http.Client, APIServer string, metadatafile string, u
 
 // readMetadataFromFile reads the metadata from the file and unmarshals it into a map.
 func readMetadataFromFile(metadatafile string) (map[string]interface{}, error) {
-	b, err := ioutil.ReadFile(metadatafile) // just pass the file name
+	b, err := os.ReadFile(metadatafile) // just pass the file name
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -330,7 +330,7 @@ func checkMetadataValidity(client *http.Client, APIServer string, metaDataMap ma
 			return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 
-	_, err = ioutil.ReadAll(resp.Body)
+	_, err = io.ReadAll(resp.Body)
 	if err != nil {
 			return err
 	}