Update gomod and vendor

vendor/github.com/moby/buildkit/session/secrets/secrets.proto

@@ -0,0 +1,19 @@
+syntax = "proto3";
+
+package moby.buildkit.secrets.v1;
+
+option go_package = "secrets";
+
+service Secrets{
+  rpc GetSecret(GetSecretRequest) returns (GetSecretResponse);
+}
+
+
+message GetSecretRequest {
+	string ID = 1;
+	map<string, string> annotations = 2;
+}
+
+message GetSecretResponse {
+	bytes data = 1;
+}