Document minimum JDK 8 update version

Closes gh-23563

Author: sbrannen

src/docs/asciidoc/overview.adoc

@@ -9,6 +9,8 @@ need to embrace the Java language in an enterprise environment, with support for
 and Kotlin as alternative languages on the JVM, and with the flexibility to create many
 kinds of architectures depending on an application's needs. As of Spring Framework 5.1,
 Spring requires JDK 8+ (Java SE 8+) and provides out-of-the-box support for JDK 11 LTS.
+Java SE 8 update 60 is suggested as the minimum patch release for Java 8, but it is
+generally recommended to use a recent patch release.
 
 Spring supports a wide range of application scenarios. In a large enterprise, applications
 often exist for a long time and have to run on a JDK and application server whose upgrade

src/docs/asciidoc/web/webflux-view.adoc

@@ -353,8 +353,9 @@ The following example shows how to set a custom render function:
 
 NOTE: Setting the `sharedEngine` property to `false` is required when using non-thread-safe
 script engines with templating libraries not designed for concurrency, such as Handlebars or
-React running on Nashorn. In that case, Java 8u60 or greater is required, due
-to https://bugs.openjdk.java.net/browse/JDK-8076099[this bug].
+React running on Nashorn. In that case, Java SE 8 update 60 is required, due to
+https://bugs.openjdk.java.net/browse/JDK-8076099[this bug], but it is generally
+recommended to use a recent Java SE patch release in any case.
 
 `polyfill.js` defines only the `window` object needed by Handlebars to run properly,
 as the following snippet shows:

src/docs/asciidoc/web/webmvc-view.adoc

@@ -793,10 +793,11 @@ The following example shows how to do so:
 	}
 ----
 
-NOTE: Setting the `sharedEngine` property to `false` is required when you use non-thread-safe
+NOTE: Setting the `sharedEngine` property to `false` is required when using non-thread-safe
 script engines with templating libraries not designed for concurrency, such as Handlebars or
-React running on Nashorn. In that case, Java 8u60 or greater is required, due
-to https://bugs.openjdk.java.net/browse/JDK-8076099[this bug].
+React running on Nashorn. In that case, Java SE 8 update 60 is required, due to
+https://bugs.openjdk.java.net/browse/JDK-8076099[this bug], but it is generally
+recommended to use a recent Java SE patch release in any case.
 
 `polyfill.js` defines only the `window` object needed by Handlebars to run properly, as follows: