Bump tinymce from 4.9.11 to 5.6.0

Bumps [tinymce](https://github.com/tinymce/tinymce-dist) from 4.9.11 to 5.6.0.
- [Release notes](https://github.com/tinymce/tinymce-dist/releases)
- [Changelog](https://github.com/tinymce/tinymce-dist/blob/master/changelog.txt)
- [Commits](https://github.com/tinymce/tinymce-dist/compare/4.9.11...5.6.0)

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

package.json

@@ -26,7 +26,7 @@
     "popper.js": "^1.16.1",
     "serialize-javascript": "^3.1.0",
     "terser": "^4.6.11",
-    "tinymce": "^4.9.11",
+    "tinymce": "^5.6.0",
     "tinymce-light-skin": "^1.3.1",
     "vue": "^2.6.11",
     "webpack": "^4.43.0",

yarn.lock

@@ -8698,10 +8698,10 @@ tinymce-light-skin@^1.3.1:
   resolved "https://registry.yarnpkg.com/tinymce-light-skin/-/tinymce-light-skin-1.3.1.tgz#fcce7a8b5761716a381f756e1ac7f47c7a41ea88"
   integrity sha512-NMmaqaZMvHeWcdJvYfNKK3wXkNkdhFjo3xswm7AiQLtU5eQHCL4li4R8+R0BRD8ejHEOG2+Tdf+NzWI4cRsa8w==
 
-tinymce@^4.9.11:
-  version "4.9.11"
-  resolved "https://registry.yarnpkg.com/tinymce/-/tinymce-4.9.11.tgz#e3dae099722294c5b8d84ba7ef18dd126de6b582"
-  integrity sha512-nkSLsax+VY5DBRjMFnHFqPwTnlLEGHCco82FwJF2JNH6W+5/ClvNC1P4uhD5lXPDNiDykSHR0XJdEh7w/ICHzA==
+tinymce@^5.6.0:
+  version "5.6.0"
+  resolved "https://registry.yarnpkg.com/tinymce/-/tinymce-5.6.0.tgz#b5eda4888e1a607ddd545619cfaa137d59de14b4"
+  integrity sha512-f8LsyT80j8hD4wrL8Sac0DWDG5k10cDyykL/qkJ6kexn1KMt7w1ByrGlUm53XCYDqtavBA5snTU7odioMwSXSQ==
 
 tmp@^0.0.33:
   version "0.0.33"