Merge pull request #7220 from magento/kh_varnish-23

Update supported versions of Varnish

Author: keharper

src/guides/v2.3/config-guide/varnish/config-varnish.md

@@ -10,7 +10,7 @@ functional_areas:
 ## Overview of the Varnish solution {#config-varnish-over}
 [Varnish Cache] is an open source web application accelerator (also referred to as an *HTTP accelerator* or *caching HTTP reverse proxy*). Varnish stores (or caches) files or fragments of files in memory; this enables Varnish to reduce the response time and network bandwidth consumption on future, equivalent requests. Unlike web servers like Apache and nginx, Varnish was designed for use exclusively with the HTTP protocol.
 
-Magento 2 supports Varnish 4.x, 5.x and 6.x
+Magento 2 supports Varnish 6.x
 
 {:.bs-callout-warning}
 We _strongly recommend_ you use Varnish in production. The built-in full-page caching (to either the file system or [database]) is much slower than Varnish, and Varnish is designed to accelerate HTTP traffic.

src/guides/v2.3/install-gde/system-requirements-tech.md

@@ -108,7 +108,7 @@ Mail Transfer Agent (MTA) or an SMTP server
 ## Technologies Magento can use
 
 *  [Redis][] versions 3.2, 4.0, 5.0 (compatible with 2.4+) for page caching and session storage. Version 5.0 is highly recommended.
-*  [Varnish]({{page.baseurl}}/config-guide/varnish/config-varnish.html) version 4.x, 5.2 or 6.2
+*  [Varnish]({{page.baseurl}}/config-guide/varnish/config-varnish.html) version 6.x (tested with 6.3.1)
 *  [Elasticsearch]({{page.baseurl}}/config-guide/elasticsearch/es-overview.html)
 
    {{site.data.var.ee}} version 2.3.x supports the following Elasticsearch versions: