Use rekor types from (unreleased) protobuf-specs

As of right now this is not in a released protobuf-specs: just preparing
for when it is

Signed-off-by: Jussi Kukkonen <[email protected]>

Author: jku

sigstore/_internal/rekor/client_v2.py

@@ -25,12 +25,12 @@
 import requests
 from cryptography.hazmat.primitives import serialization
 from cryptography.x509 import Certificate
+from sigstore_protobuf_specs.dev.sigstore.common import v1 as common_v1
+from sigstore_protobuf_specs.dev.sigstore.rekor import v2
+from sigstore_protobuf_specs.io import intoto
 
 from sigstore._internal import USER_AGENT
 from sigstore._internal.rekor import EntryRequest, RekorLogSubmitter
-from sigstore._internal.rekor.v2_types.dev.sigstore.common import v1 as common_v1
-from sigstore._internal.rekor.v2_types.dev.sigstore.rekor import v2
-from sigstore._internal.rekor.v2_types.io import intoto as v2_intoto
 from sigstore.dsse import Envelope
 from sigstore.hashes import Hashed
 from sigstore.models import LogEntry
@@ -126,11 +126,11 @@ def _build_dsse_request(
         """
         req = v2.CreateEntryRequest(
             dsse_request_v0_0_2=v2.DsseRequestV002(
-                envelope=v2_intoto.Envelope(
+                envelope=intoto.Envelope(
                     payload=envelope._inner.payload,
                     payload_type=envelope._inner.payload_type,
                     signatures=[
-                        v2_intoto.Signature(
+                        intoto.Signature(
                             keyid=signature.keyid,
                             sig=signature.sig,
                         )