Fix Readiness check (#8681)

- Remove goroutine-check in Readiness check
- Bring in quorum check for readiness

Fixes #8385

Co-authored-by: Harshavardhana <harsha@minio.io>

cmd/gateway/azure/gateway-azure.go

@@ -1296,3 +1296,8 @@ func (a *azureObjects) DeleteBucketPolicy(ctx context.Context, bucket string) er
 func (a *azureObjects) IsCompressionSupported() bool {
 	return false
 }
+
+// IsReady returns whether the layer is ready to take requests.
+func (a *azureObjects) IsReady(ctx context.Context) bool {
+	return minio.IsBackendOnline(ctx, a.httpClient, a.endpoint)
+}