Update Jenkins LTS versions to 2.452.1 in various parts of the documentation

content/doc/developer/plugin-development/choosing-jenkins-baseline.adoc

@@ -13,7 +13,7 @@ You need to balance compatibility and features:
 In particular, the LTS Release Line is based on slightly older releases to provide a more stable experience for conservative users.
 * *Building against recent Jenkins versions* allows you to use recently added core features and API from your plugin. 
 You will also use that newer version for `mvn hpi:run`, so it may be easier to test your plugin with newer Jenkins releases. 
-* *Do not use versions no longer supported by the update center*, which is currently anything older than 2.393 for weekly releases, and 2.387.2 for LTS releases.
+* *Do not use versions no longer supported by the update center*, which is currently anything older than 2.400 for weekly releases, and 2.387.2 for LTS releases.
   Note that the lowest supported version changes about every week (weekly release) or every month (LTS release), so these specific versions will be a bad choice soon.
 * *Prefer an LTS version over weekly versions.*
 ** If you are based on the _currently active_ LTS line,
@@ -36,8 +36,8 @@ Something around 1 year old that does not have too many detached plugins makes a
 
 ## Currently recommended versions
 
-At the moment, the Jenkins releases *2.414.3 and 2.426.3* make good core dependencies.
-You could also consider *2.440.1* if there are specific reasons, like new features, to want something newer.
+At the moment, the Jenkins releases *2.426.3 and 2.440.3* make good core dependencies.
+You could also consider *2.452.1* if there are specific reasons, like new features, to want something newer.
 
 ## Changing the minimum required version
 
@@ -46,6 +46,6 @@ Set the `jenkins.version` property in `pom.xml` to the version you need to depen
 [source,xml]
 ----
 <properties>
-  <jenkins.version>2.426.3</jenkins.version>
+  <jenkins.version>2.440.3</jenkins.version>
 </properties>
 ----

content/doc/developer/tutorial-improve/update-base-jenkins-version.adoc

@@ -5,7 +5,7 @@ title: Update Jenkins version
 
 :modified-files: pom.xml
 :task-identifier: require-newer-core
-:task-description: Require 2.426.3 as minimum Jenkins version
+:task-description: Require 2.440.3 as minimum Jenkins version
 
 = Update minimum Jenkins version
 
@@ -26,7 +26,7 @@ Update the minimum required Jenkins version by setting a `jenkins.version` value
 [source,xml,subs="attributes+"]
 ----
    <properties>
-     <jenkins.version>2.426.3</jenkins.version>
+     <jenkins.version>2.440.3</jenkins.version>
    </properties>
 ----