rebase: bump google.golang.org/grpc from 1.66.2 to 1.67.0

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.66.2 to 1.67.0.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](https://github.com/grpc/grpc-go/compare/v1.66.2...v1.67.0)

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

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

vendor/google.golang.org/grpc/balancer/base/balancer.go

@@ -36,7 +36,7 @@ type baseBuilder struct {
 	config        Config
 }
 
-func (bb *baseBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
+func (bb *baseBuilder) Build(cc balancer.ClientConn, _ balancer.BuildOptions) balancer.Balancer {
 	bal := &baseBalancer{
 		cc:            cc,
 		pickerBuilder: bb.pickerBuilder,
@@ -259,6 +259,6 @@ type errPicker struct {
 	err error // Pick() always returns this err.
 }
 
-func (p *errPicker) Pick(info balancer.PickInfo) (balancer.PickResult, error) {
+func (p *errPicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
 	return balancer.PickResult{}, p.err
 }

vendor/google.golang.org/grpc/balancer/pickfirst/pickfirst.go

@@ -50,7 +50,7 @@ const (
 
 type pickfirstBuilder struct{}
 
-func (pickfirstBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
+func (pickfirstBuilder) Build(cc balancer.ClientConn, _ balancer.BuildOptions) balancer.Balancer {
 	b := &pickfirstBalancer{cc: cc}
 	b.logger = internalgrpclog.NewPrefixLogger(logger, fmt.Sprintf(logPrefix, b))
 	return b