Bump org.kordamp.ikonli:ikonli-javafx from 12.3.1 to 12.4.0 (#12987)

Bumps [org.kordamp.ikonli:ikonli-javafx](https://github.com/kordamp/ikonli) from 12.3.1 to 12.4.0.
- [Release notes](https://github.com/kordamp/ikonli/releases)
- [Changelog](https://github.com/kordamp/ikonli/blob/master/jreleaser.yml)
- [Commits](kordamp/ikonli@v12.3.1...v12.4.0)

---
updated-dependencies:
- dependency-name: org.kordamp.ikonli:ikonli-javafx
  dependency-version: 12.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

build.gradle

@@ -235,7 +235,7 @@ dependencies {
     implementation('org.jabref:afterburner.fx:2.0.0') {
         exclude group: 'org.openjfx'
     }
-    implementation 'org.kordamp.ikonli:ikonli-javafx:12.3.1'
+    implementation 'org.kordamp.ikonli:ikonli-javafx:12.4.0'
     implementation 'org.kordamp.ikonli:ikonli-materialdesign2-pack:12.3.1'
     implementation 'com.github.sialcasa.mvvmFX:mvvmfx-validation:f195849ca9' //jitpack
     implementation 'de.saxsys:mvvmfx:1.8.0'