Fix linting and unit tests

Signed-off-by: Andrew Keesler <akeesler@vmware.com>

internal/controller/supervisorconfig/dynamic_config_watcher.go

@@ -15,10 +15,6 @@ import (
 	"go.pinniped.dev/internal/controllerlib"
 )
 
-const (
-	issuerConfigMapKey = "issuer"
-)
-
 // IssuerSetter can be notified of a valid issuer with its SetIssuer function. If there is no
 // longer any valid issuer, then nil can be passed to this interface.
 //
@@ -79,7 +75,13 @@ func (c *dynamicConfigWatcherController) Sync(ctx controllerlib.Context) error {
 			"oidcproviderconfig",
 			klog.KRef(ctx.Key.Namespace, ctx.Key.Name),
 		)
-		c.issuerSetter.SetIssuer(nil)
+		if err := c.issuerSetter.SetIssuer(nil); err != nil {
+			klog.InfoS(
+				"dynamicConfigWatcherController Sync failed to set issuer",
+				"err",
+				err,
+			)
+		}
 		return nil
 	}
 

internal/oidc/discovery/discovery_test.go

@@ -93,7 +93,8 @@ func TestDiscovery(t *testing.T) {
 		test := test
 		t.Run(test.name, func(t *testing.T) {
 			p := issuerprovider.New()
-			p.SetIssuer(test.issuer)
+			err := p.SetIssuer(test.issuer)
+			require.NoError(t, err)
 
 			handler := New(p)
 			req := httptest.NewRequest(test.method, test.path, nil)

internal/oidc/issuerprovider/issuerprovider_test.go

@@ -1,3 +1,6 @@
+// Copyright 2020 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
 package issuerprovider
 
 import (
@@ -62,6 +65,7 @@ func TestProvider(t *testing.T) {
 		},
 	}
 	for _, tt := range tests {
+		tt := tt
 		t.Run(tt.name, func(t *testing.T) {
 			p := New()
 			err := p.SetIssuer(tt.issuer)