Clarify that shutdown endpoint only works in jar packaging

Closes gh-17398

spring-boot-project/spring-boot-docs/src/docs/asciidoc/actuator/endpoints.adoc

@@ -76,15 +76,16 @@ The following technology-agnostic endpoints are available:
 
 | `sessions`
 | Allows retrieval and deletion of user sessions from a Spring Session-backed session store.
-  Requires a servlet-based web application that uses Spring Session.
+Requires a servlet-based web application that uses Spring Session.
 
 | `shutdown`
 | Lets the application be gracefully shutdown.
-  Disabled by default.
+Only works when using jar packaging.
+Disabled by default.
 
 | `startup`
 | Shows the <<features#features.spring-application.startup-tracking,startup steps data>> collected by the `ApplicationStartup`.
-  Requires the `SpringApplication` to be configured with a `BufferingApplicationStartup`.
+Requires the `SpringApplication` to be configured with a `BufferingApplicationStartup`.
 
 | `threaddump`
 | Performs a thread dump.

spring-boot-project/spring-boot-docs/src/docs/asciidoc/authors.adoc

@@ -1 +1 @@
-Phillip Webb; Dave Syer; Josh Long; Stéphane Nicoll; Rob Winch; Andy Wilkinson; Marcel Overdijk; Christian Dupuis; Sébastien Deleuze; Michael Simons; Vedran Pavić; Jay Bryant; Madhura Bhave; Eddú Meléndez; Scott Frederick
+Phillip Webb; Dave Syer; Josh Long; Stéphane Nicoll; Rob Winch; Andy Wilkinson; Marcel Overdijk; Christian Dupuis; Sébastien Deleuze; Michael Simons; Vedran Pavić; Jay Bryant; Madhura Bhave; Eddú Meléndez; Scott Frederick; Moritz Halbritter