Update Platform Version of JetBrains Backend Plugin (EAP) to

Author: roboquat

components/ide/jetbrains/backend-plugin/gradle-latest.properties

@@ -2,10 +2,10 @@
 # See https://plugins.jetbrains.com/docs/intellij/build-number-ranges.html
 # for insight into build numbers and IntelliJ Platform versions.
 # revert pluginSinceBuild if it's unnecessary
-pluginSinceBuild=243.15521
+pluginSinceBuild=243.19420
 pluginUntilBuild=243.*
 # Plugin Verifier integration -> https://github.com/JetBrains/gradle-intellij-plugin#plugin-verifier-dsl
 # See https://jb.gg/intellij-platform-builds-list for available build versions.
 pluginVerifierIdeVersions=2024.3
 # Version from "com.jetbrains.intellij.idea" which can be found at https://www.jetbrains.com/intellij-repository/snapshots
-platformVersion=243.15521.24
+platformVersion=243.19420.21