dependabot: bump de.undercouch.download from 5.3.0 to 5.6.0 (#1333)

Bumps de.undercouch.download from 5.3.0 to 5.6.0.

---
updated-dependencies:
- dependency-name: de.undercouch.download
  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>

build.gradle

@@ -85,7 +85,7 @@ buildscript {
 }
 
 plugins {
-    id "de.undercouch.download" version "5.3.0"
+    id "de.undercouch.download" version "5.6.0"
     id "com.netflix.nebula.ospackage" version "11.10.1"
     id "com.dorongold.task-tree" version "2.1.1"
 }