Bump checkstyle from 8.39 to 8.40 (#7404)

Bumps [checkstyle](https://github.com/checkstyle/checkstyle) from 8.39 to 8.40.
- [Release notes](https://github.com/checkstyle/checkstyle/releases)
- [Commits](checkstyle/checkstyle@checkstyle-8.39...checkstyle-8.40)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

build.gradle

@@ -211,7 +211,7 @@ dependencies {
     testImplementation "org.testfx:testfx-junit5:4.0.17-alpha-SNAPSHOT"
     testImplementation "org.hamcrest:hamcrest-library:2.2"
 
-    checkstyle 'com.puppycrawl.tools:checkstyle:8.39'
+    checkstyle 'com.puppycrawl.tools:checkstyle:8.40'
     xjc group: 'org.glassfish.jaxb', name: 'jaxb-xjc', version: '2.3.3'
 }