chore: fix lint errors from newer golangci-lint (#7958)

Signed-off-by: Faiyaz Rahman <faiyazrahman03@gmail.com>

caddytest/caddytest.go

@@ -340,7 +340,6 @@ func CreateTestingTransport() *http.Transport {
 	dialer := net.Dialer{
 		Timeout:   5 * time.Second,
 		KeepAlive: 5 * time.Second,
-		DualStack: true,
 	}
 
 	dialContext := func(ctx context.Context, network, addr string) (net.Conn, error) {

modules/caddyhttp/fileserver/matcher.go

@@ -622,7 +622,7 @@ func isCELTryFilesLiteral(e ast.Expr) bool {
 					return false
 				}
 			case "try_policy", "root":
-				if !(isCELStringExpr(mapVal)) {
+				if !isCELStringExpr(mapVal) {
 					return false
 				}
 			default:

modules/caddytls/fileloader.go

@@ -117,6 +117,6 @@ func (fl FileLoader) LoadCertificates() ([]Certificate, error) {
 
 // Interface guard
 var (
-	_ CertificateLoader = (FileLoader)(nil)
-	_ caddy.Provisioner = (FileLoader)(nil)
+	_ CertificateLoader = FileLoader(nil)
+	_ caddy.Provisioner = FileLoader(nil)
 )

modules/caddytls/folderloader.go

@@ -175,6 +175,6 @@ func tlsCertFromCertAndKeyPEMBundle(bundle []byte) (tls.Certificate, error) {
 }
 
 var (
-	_ CertificateLoader = (FolderLoader)(nil)
-	_ caddy.Provisioner = (FolderLoader)(nil)
+	_ CertificateLoader = FolderLoader(nil)
+	_ caddy.Provisioner = FolderLoader(nil)
 )

modules/caddytls/pemloader.go

@@ -89,6 +89,6 @@ func (pl PEMLoader) LoadCertificates() ([]Certificate, error) {
 
 // Interface guard
 var (
-	_ CertificateLoader = (PEMLoader)(nil)
-	_ caddy.Provisioner = (PEMLoader)(nil)
+	_ CertificateLoader = PEMLoader(nil)
+	_ caddy.Provisioner = PEMLoader(nil)
 )