Extend set of messages muted by elasticsearch_mute_deprecation_warnings

Refers to Graylog2/support#54

## What?

#10239 introduced the config file setting `elasticsearch_mute_deprecation_warnings` to GL 5.1. When enabled it suppresses certain noisy ES6 deprecation warnings.
ES7 emits additional deprecation warnings which customers would also like to mute. Specifically this one:

> 2024-05-30T02:00:05.774+02:00 WARN [RestClient] request [PUT https://vux5646.lvm.de:443/gl-failures_88?master_timeout=30s&timeout=30s] returned 1 warnings: [299 Elasticsearch-7.10.2-747e1cc71def077253878a59143c1f785afa92b9 "index [gl-failures_88] matches multiple legacy templates [generic-template, gl-failures-template], composable templates will only match a single template"]

## Why?

Clutters the log

## Your Environment

* Graylog Version: 5.2, 6.0
* OpenSearch Version: ES7
* MongoDB Version:
* Operating System:
* Browser version: