Bump tinymce from 4.9.11 to 5.4.2

Bumps [tinymce](https://github.com/tinymce/tinymce-dist) from 4.9.11 to 5.4.2.
- [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...5.4.2)

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

package.json

@@ -26,7 +26,7 @@
     "jquery": "^3.5.0",
     "metrics-graphics": "mozilla/metrics-graphics#2.15.x",
     "shariff": "^3.2.1",
-    "tinymce": "^4.9.11"
+    "tinymce": "^5.4.2"
   },
   "engines": {
     "yarn": ">= 1.0.0"

yarn.lock

@@ -423,10 +423,10 @@ shariff@^3.2.1:
     "@fortawesome/fontawesome-free" "^5.8.2"
     jquery "^3.4.1"
 
-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@^5.4.2:
+  version "5.4.2"
+  resolved "https://registry.yarnpkg.com/tinymce/-/tinymce-5.4.2.tgz#a1df417ea7e85697c2932269f7f93fbef30d4502"
+  integrity sha512-MRquvKxI28AiSn2ikypgJFD7LH4mQZLtgFn+yROF1bTFp92MdlLeGBrI38/O5mej3cvz27g3Pgr+3MShepbJ+w==
 
 xmlhttprequest@1:
   version "1.8.0"