Chore: Update grafana-plugin-sdk (#84289)

pkg/services/datasources/service/datasource.go

@@ -484,7 +484,7 @@ func (s *Service) httpClientOptions(ctx context.Context, ds *datasources.DataSou
 
 	opts := &sdkhttpclient.Options{
 		Timeouts: timeouts,
-		Headers:  s.getCustomHeaders(ds.JsonData, decryptedValues),
+		Header:   s.getCustomHeaders(ds.JsonData, decryptedValues),
 		Labels: map[string]string{
 			"datasource_type": ds.Type,
 			"datasource_name": ds.Name,
@@ -654,8 +654,8 @@ func (s *Service) getTimeout(ds *datasources.DataSource) time.Duration {
 
 // getCustomHeaders returns a map with all the to be set headers
 // The map key represents the HeaderName and the value represents this header's value
-func (s *Service) getCustomHeaders(jsonData *simplejson.Json, decryptedValues map[string]string) map[string]string {
-	headers := make(map[string]string)
+func (s *Service) getCustomHeaders(jsonData *simplejson.Json, decryptedValues map[string]string) http.Header {
+	headers := make(http.Header)
 	if jsonData == nil {
 		return headers
 	}
@@ -680,7 +680,7 @@ func (s *Service) getCustomHeaders(jsonData *simplejson.Json, decryptedValues ma
 		}
 
 		if val, ok := decryptedValues[headerValueSuffix]; ok {
-			headers[key] = val
+			headers.Add(key, val)
 		}
 	}
 
@@ -769,7 +769,7 @@ func readQuotaConfig(cfg *setting.Cfg) (*quota.Map, error) {
 }
 
 // CustomerHeaders returns the custom headers specified in the datasource. The context is used for the decryption operation that might use the store, so consider setting an acceptable timeout for your use case.
-func (s *Service) CustomHeaders(ctx context.Context, ds *datasources.DataSource) (map[string]string, error) {
+func (s *Service) CustomHeaders(ctx context.Context, ds *datasources.DataSource) (http.Header, error) {
 	values, err := s.SecretsService.DecryptJsonData(ctx, ds.SecureJsonData)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get custom headers: %w", err)