build(deps): bump google.golang.org/protobuf from 1.25.0 to 1.26.0

Bumps [google.golang.org/protobuf](https://github.com/protocolbuffers/protobuf-go) from 1.25.0 to 1.26.0.
- [Release notes](https://github.com/protocolbuffers/protobuf-go/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf-go/blob/master/release.bash)
- [Commits](https://github.com/protocolbuffers/protobuf-go/compare/v1.25.0...v1.26.0)

---
updated-dependencies:
- dependency-name: google.golang.org/protobuf
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/google.golang.org/protobuf/internal/impl/encode.go

@@ -79,8 +79,9 @@ func (mi *MessageInfo) sizePointerSlow(p pointer, opts marshalOptions) (size int
 		size += f.funcs.size(fptr, f, opts)
 	}
 	if mi.unknownOffset.IsValid() {
-		u := *p.Apply(mi.unknownOffset).Bytes()
-		size += len(u)
+		if u := mi.getUnknownBytes(p); u != nil {
+			size += len(*u)
+		}
 	}
 	if mi.sizecacheOffset.IsValid() {
 		if size > math.MaxInt32 {
@@ -141,8 +142,9 @@ func (mi *MessageInfo) marshalAppendPointer(b []byte, p pointer, opts marshalOpt
 		}
 	}
 	if mi.unknownOffset.IsValid() && !mi.isMessageSet {
-		u := *p.Apply(mi.unknownOffset).Bytes()
-		b = append(b, u...)
+		if u := mi.getUnknownBytes(p); u != nil {
+			b = append(b, (*u)...)
+		}
 	}
 	return b, nil
 }