RHIDP-6568: Add info about TechDocs builder

Author: linfraze

Diff for: modules/customizing/proc-customizing-rhdh-metadata-card.adoc

@@ -25,8 +25,13 @@ buildInfo:
 where
 
 _<build_info_card_title>_ :: Specifies the title that you want to display in the *{product-very-short} Build info* card.
-_<techdocs_builder>_ :: Specifies the TechDocs builder that you want to use, for example, `local`.
-_<authentication_provider>_ :: Specifies the authentication provider that you want to use, for example, `GitHub` or `GitLab`.
+_<techdocs_builder>_ :: Specifies whether to generate and publish the docs or to only fetch the docs when using the default build strategy. Example values are `local` or `external`.
+_<authentication_provider>_ :: Specifies the authentication provider that you want to use. Example values are `GitHub` or `GitLab`.
++
+[NOTE]
+====
+If you want to generate and publish the docs when using the default build strategy, set the `techdocs.builder` field to `local` in your app-config.yaml file. If you only want to fetch the docs without generating and publishing them, set the `techdocs.builder` field to `external`.
+====
 
 .Result
 The *Settings* page displays a card with a custom title and custom build information about your {product} instance.