[DOCS] Augment installation warnings (#112756)

Author: lcawl

docs/plugins/install_remove.asciidoc

@@ -4,7 +4,7 @@
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of the Elastic Stack has not yet been released.
+WARNING: Version {version} of the Elastic Stack has not yet been released. The plugin might not be available.
 
 endif::[]
 

docs/reference/setup/install/deb.asciidoc

@@ -108,7 +108,7 @@ include::skip-set-kernel-parameters.asciidoc[]
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of Elasticsearch has not yet been released.
+WARNING: Version {version} of Elasticsearch has not yet been released. The package might not be available.
 
 endif::[]
 

docs/reference/setup/install/rpm.asciidoc

@@ -101,7 +101,7 @@ endif::[]
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of Elasticsearch has not yet been released.
+WARNING: Version {version} of Elasticsearch has not yet been released. The RPM might not be available.
 
 endif::[]
 

docs/reference/setup/install/targz.asciidoc

@@ -21,7 +21,7 @@ see the <<jvm-version, JVM version requirements>>
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of {es} has not yet been released.
+WARNING: Version {version} of {es} has not yet been released. The archive might not be available.
 
 endif::[]
 
@@ -44,7 +44,7 @@ cd elasticsearch-{version}/ <2>
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of {es} has not yet been released.
+WARNING: Version {version} of {es} has not yet been released. The archive might not be available.
 
 endif::[]
 

docs/reference/setup/install/zip-windows.asciidoc

@@ -31,7 +31,7 @@ see the <<jvm-version, JVM version requirements>>
 
 ifeval::["{release-state}"=="unreleased"]
 
-WARNING: Version {version} of {es} has not yet been released.
+WARNING: Version {version} of {es} has not yet been released. The archive might not be available.
 
 endif::[]