Fix retrieval of cluster settings when determining deprecation logging status

[cjcenizal]

There's a typo in the UA logic on these lines:

kibana/x-pack/plugins/upgrade_assistant/server/lib/es_deprecation_logging_apis.ts

Line 54 in 9911883

const clusterDeprecationLoggingEnabled = ['default', 'persistent', 'transient'].reduce(

kibana/x-pack/plugins/upgrade_assistant/server/lib/es_deprecation_logging_apis.ts

Line 64 in 9911883

const deprecationLogLevel = ['default', 'persistent', 'transient'].reduce(

in both cases, default should be defaults. You can see that when we retrieve cluster settings with the defaults, they're namespaced under the defaults object:

This should fix a bug that @jakelandis and @pgomulka found, in which deprecation logging should be enabled by default, but UA reports it as disabled by default.

[elasticmachine]

Pinging @elastic/kibana-stack-management (Team:Stack Management)