FAB-14035 Add tests for configtxgen encoder

The tests currently covering the configtxgen encoder are almost entirely
based on sample config and really cover almost none of the non-green
paths.  This CR simply replaces all of the existing test with a new
ginkgo suite covering 98.4% of lines.  The uncovered lines are
unreachable and will be removed in a later CR.

Change-Id: I2d2bfd7f4437511258a7832a7df0735fab2a2fbf
Signed-off-by: Jason Yellick <jyellick@us.ibm.com>

common/tools/configtxgen/encoder/encoder_suite_test.go

@@ -0,0 +1,26 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package encoder_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/hyperledger/fabric/common/crypto"
+)
+
+//go:generate counterfeiter -o mock/local_signer.go --fake-name LocalSigner . localSigner
+type localSigner interface {
+	crypto.LocalSigner
+}
+
+func TestEncoder(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Encoder Suite")
+}