Update drupal/dropzonejs requirement from 2.6.0 to 2.7.0

Updates the requirements on drupal/dropzonejs to permit the latest version.

---
updated-dependencies:
- dependency-name: drupal/dropzonejs
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

composer.json

@@ -70,7 +70,7 @@
         "drupal/ctools": "3.11.0",
         "drupal/devel": "4.1.5",
         "drupal/diff": "1.0.0",
-        "drupal/dropzonejs": "2.6.0",
+        "drupal/dropzonejs": "2.7.0",
         "drupal/ds": "3.15.0",
         "drupal/dynamic_entity_reference": "1.16.0",
         "drupal/embed": "1.6.0",