fix: package.json & yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-TINYMCE-6501006
- https://snyk.io/vuln/SNYK-JS-TINYMCE-6501605

package.json

@@ -94,7 +94,7 @@
     "textcomplete": "^0.18.2",
     "timeago": "^1.6.7",
     "timepicker": "^1.14.1",
-    "tinymce": "^5.10.9",
+    "tinymce": "^7.0.0",
     "video.js": "^7.21.5",
     "vue-flatpickr-component": "^9.0.8",
     "vue-i18n": "9.9.0",