[Vendor] Update go-redis to v8.5.0 (#13749)

* Update go-redis to v8.4.0

* github.com/go-redis/redis/v8  v8.4.0 -> v8.5.0

* Apply suggestions from code review

Co-authored-by: zeripath <art27@cantab.net>

* TODO

* Use the Queue termination channel as the default context for pushes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* missed one

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: zeripath <art27@cantab.net>

vendor/github.com/go-redis/redis/v8/internal/util.go

@@ -0,0 +1,73 @@
+package internal
+
+import (
+	"context"
+	"time"
+
+	"github.com/go-redis/redis/v8/internal/proto"
+	"github.com/go-redis/redis/v8/internal/util"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/trace"
+)
+
+func Sleep(ctx context.Context, dur time.Duration) error {
+	return WithSpan(ctx, "time.Sleep", func(ctx context.Context, span trace.Span) error {
+		t := time.NewTimer(dur)
+		defer t.Stop()
+
+		select {
+		case <-t.C:
+			return nil
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	})
+}
+
+func ToLower(s string) string {
+	if isLower(s) {
+		return s
+	}
+
+	b := make([]byte, len(s))
+	for i := range b {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			c += 'a' - 'A'
+		}
+		b[i] = c
+	}
+	return util.BytesToString(b)
+}
+
+func isLower(s string) bool {
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			return false
+		}
+	}
+	return true
+}
+
+//------------------------------------------------------------------------------
+
+var tracer = otel.Tracer("github.com/go-redis/redis")
+
+func WithSpan(ctx context.Context, name string, fn func(context.Context, trace.Span) error) error {
+	if span := trace.SpanFromContext(ctx); !span.IsRecording() {
+		return fn(ctx, span)
+	}
+
+	ctx, span := tracer.Start(ctx, name)
+	defer span.End()
+
+	return fn(ctx, span)
+}
+
+func RecordError(ctx context.Context, span trace.Span, err error) error {
+	if err != proto.Nil {
+		span.RecordError(err)
+	}
+	return err
+}