[#44] add tracing support refactoring

Signed-off-by: Pavel Pogodaev <p.pogodaev@yadro.com>

tokens/bearer-token_test.go

@@ -3,6 +3,7 @@
 package tokens
 
 import (
+	"context"
 	"encoding/base64"
 	"testing"
 
@@ -153,10 +154,11 @@ func Test_checkAndPropagateBearerToken(t *testing.T) {
 	ctx := makeTestRequest(t64, "")
 
 	// Expect to see the token within the context.
-	require.NoError(t, StoreBearerToken(ctx))
+	appCtx, err := StoreBearerTokenAppCtx(ctx, context.Background())
+	require.NoError(t, err)
 
 	// Expect to see the same token without errors.
-	actual, err := LoadBearerToken(ctx)
+	actual, err := LoadBearerToken(appCtx)
 	require.NoError(t, err)
 	require.Equal(t, tkn, actual)
 }