Correctly load private key by not decoding PEM 2x

Signed-off-by: Hidde Beydals <hello@hidde.co>

pkg/manifestgen/sourcesecret/sourcesecret_test.go

@@ -0,0 +1,40 @@
+/*
+Copyright 2021 The Flux authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package sourcesecret
+
+import (
+	"io/ioutil"
+	"reflect"
+	"testing"
+)
+
+func Test_loadKeyPair(t *testing.T) {
+	pk, _ := ioutil.ReadFile("testdata/rsa")
+	ppk, _ := ioutil.ReadFile("testdata/rsa.pub")
+
+	got, err := loadKeyPair("testdata/rsa")
+	if err != nil {
+		t.Errorf("loadKeyPair() error = %v", err)
+		return
+	}
+	if !reflect.DeepEqual(got.PrivateKey, pk) {
+		t.Errorf("PrivateKey %s != %s", got.PrivateKey, pk)
+	}
+	if !reflect.DeepEqual(got.PublicKey, ppk) {
+		t.Errorf("PublicKey %s != %s", got.PublicKey, ppk)
+	}
+}