fix: Different ratelimits for the same route (implement discord buckets) (#1546)

* Don't disable when there's no resetTick

Sometimes Discord won't send any ratelimit headers, disabling the semaphore for endpoints that should have them.

* Undo changes and change comment

* Add HttpMethod to BucketIds

* Add X-RateLimit-Bucket

* BucketId changes

- BucketId is it's own class now
- Add WebhookId as a major parameter
- Add shared buckets using the hash and major parameters

* Add webhookId to BucketIds

* Update BucketId and redirect requests

* General bugfixes

* Assign semaphore and follow the same standard as Reset for ResetAfter

src/Discord.Net.Webhook/DiscordWebhookClient.cs

@@ -77,9 +77,9 @@ namespace Discord.Webhook
             ApiClient.RequestQueue.RateLimitTriggered += async (id, info) =>
             {
                 if (info == null)
-                    await _restLogger.VerboseAsync($"Preemptive Rate limit triggered: {id ?? "null"}").ConfigureAwait(false);
+                    await _restLogger.VerboseAsync($"Preemptive Rate limit triggered: {id?.ToString() ?? "null"}").ConfigureAwait(false);
                 else
-                    await _restLogger.WarningAsync($"Rate limit triggered: {id ?? "null"}").ConfigureAwait(false);
+                    await _restLogger.WarningAsync($"Rate limit triggered: {id?.ToString() ?? "null"}").ConfigureAwait(false);
             };
             ApiClient.SentRequest += async (method, endpoint, millis) => await _restLogger.VerboseAsync($"{method} {endpoint}: {millis} ms").ConfigureAwait(false);
         }