Previously a data frame transform would check whether the
source index was changed every 10 seconds. Sometimes it
may be desirable for the check to be done less frequently.
This commit increases the default to 60 seconds but also
allows the frequency to be overridden by a setting in the
data frame transform config.
* [ML][Data Frame] adds new pipeline field to dest config (#43124)
* [ML][Data Frame] adds new pipeline field to dest config
* Adding pipeline support to _preview
* removing unused import
* moving towards extracting _source from pipeline simulation
* fixing permission requirement, adding _index entry to doc
* adjusting for java 8 compatibility
* adjusting bwc serialization version to 7.3.0
* [ML] adding pivot.size option for setting paging size
* Changing field name to address PR comments
* fixing ctor usage
* adjust hlrc for field name change
* [ML] make source and dest objects in the transform config
* addressing PR comments
* Fixing compilation post merge
* adding comment for Arrays.hashCode
* addressing changes for moving dest to object
* fixing data_frame yml tests
* fixing API test