Log prometheus config reload error instead of stopping sidecar

Signed-off-by: Max Neverov <neverov.max@gmail.com>

pkg/reloader/reloader.go

@@ -218,9 +218,7 @@ func (r *Reloader) Watch(ctx context.Context) error {
 		}
 
 		if err := r.apply(ctx); err != nil {
-			// Critical error.
-			// TODO(bwplotka): There is no need to get process down in this case and decrease availability, handle the error in different way.
-			return err
+			level.Error(r.logger).Log("msg", "apply error", "err", err)
 		}
 	}
 }