add merge filters before building cluster filters (#55815)

[wdongyu]

Currently allocation filtering works only on delta settings. For example:

1. we first set cluster.routing.allocation.exclude.zone to us-east-1a to allocate shards to all nodes not in zone us-east-1a.
2. Then we update cluster.routing.allocation.exclude.rack to rack-id. At this point, shards will relocate to nodes not in rack rack-id, ignoring the zone tag which we first set.

The reason for this bug is, when updating cluster settings for cluster require/include/exclude filters, AffixMapUpdateConsumer is only passing setting deltas, then FilterAllocationDecider rebuilds new filters using the settings deltas.

To fix this, we can merge the incoming include/exclude/require delta filters with the existing ones, and use the new merge filters to build cluster include/exclude/require filters. In this way, cluster require/include/exclude filters will include all cluster settings we have set instead of the delta ones.

ISSUE: #55815

[elasticsearchmachine]

Pinging @elastic/es-distributed (Team:Distributed)

[wdongyu]

Pinging @nik9000 @kingherc