fix(e2e): use proto.String instead of nonexistent shared.Ptr

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: whites11

flow/e2e/clickhouse_tls_test.go

@@ -6,10 +6,10 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/proto"
 
 	connclickhouse "github.com/PeerDB-io/peerdb/flow/connectors/clickhouse"
 	"github.com/PeerDB-io/peerdb/flow/generated/protos"
-	"github.com/PeerDB-io/peerdb/flow/shared"
 )
 
 // TestClickHouseTLSDirectory verifies that connclickhouse.Connect works
@@ -33,7 +33,7 @@ func TestClickHouseTLSDirectory(t *testing.T) {
 		User:                    "peerdb_tls",
 		Database:                "default",
 		DisableTls:              false,
-		TlsCertificateDirectory: shared.Ptr(certDir),
+		TlsCertificateDirectory: proto.String(certDir),
 	}
 
 	conn, err := connclickhouse.Connect(t.Context(), nil, config)