chore(deps): update plugin idea-ext to v1.4

Author: renovate[bot]

gradle/libs.versions.toml

@@ -42,4 +42,4 @@ checkerqual = "org.checkerframework:checker-qual:3.53.0"
 blossom = { id = "net.kyori.blossom", version.ref = "blossom" }
 shadow = { id = "com.gradleup.shadow", version.ref = "shadow" }
 runvelocity = { id = "xyz.jpenilla.run-velocity", version.ref = "runvelocity" }
-idea-ext = { id = "org.jetbrains.gradle.plugin.idea-ext", version = "1.3" }
+idea-ext = { id = "org.jetbrains.gradle.plugin.idea-ext", version = "1.4" }