Improve error text when elasticsearch is unavailable.

Review Request #12888 — Created March 14, 2023 and submitted — Latest diff uploaded


Review Board


When validating the Elasticsearch configuration, we'd check if the
elasticsearch module was available and was of a compatible version. If
either failed, we'd display a generic error about ensuring you have a
compatible elasticsearch.

This change updates validation to show an error specific to each case.
Both include the list of packages to install for Elasticsearch support.

Unit tests have been added to ensure validation works and to track any
changes to our list of compatible versions.

Manually tested this without elasticsearch installed, and with an
incompatible version.

Unit tests passed.