slogr: fix unintended API break in v0.8.0

logr v0.7.0 had slogr.NewSlogHandler. We must keep that function for API
compatibility. https://github.com/go-logr/logr/pull/237/files#r1434203442
accidentally renamed it.

slogr/slogr.go

@@ -40,10 +40,10 @@ func NewLogr(handler slog.Handler) logr.Logger {
 	return logr.FromSlogHandler(handler)
 }
 
-// ToSlogHandler returns a slog.Handler which writes to the same sink as the logr.Logger.
+// NewSlogHandler returns a slog.Handler which writes to the same sink as the logr.Logger.
 //
 // Deprecated: use [logr.ToSlogHandler] instead.
-func ToSlogHandler(logger logr.Logger) slog.Handler {
+func NewSlogHandler(logger logr.Logger) slog.Handler {
 	return logr.ToSlogHandler(logger)
 }