Custom tokenfilters in the _analyze endpoint cannot refer to other tokenfilters #32154
Description
The multiplexing tokenfilter and the (soon to be added) conditional tokenfilter both refer to other tokenfilters in their definitions. In the normal way of things, these are built by the AnalysisRegistry, but the _analyze endpoint allows the creation of custom tokenfilters without reference to an index, and this currently does not correctly handle these referring filters. This means that a multiplexer or conditional filter built against the _analyze endpoint will not apply any of their child filters to the tokenstream.