remove CKEditor 4 (contrib) and Convert Entity Media Embed

Now that we've switched to CK5 we can remove the contrib module for CK4. At this time, we should be safe to remove the Convert Entity Media Embed module as well.

vendor/composer/installed.json

@@ -2300,53 +2300,6 @@
             },
             "install-path": "../../web/modules/config_ignore"
         },
-        {
-            "name": "drupal/convert_entity_media_embed",
-            "version": "1.0.0-alpha5",
-            "version_normalized": "1.0.0.0-alpha5",
-            "source": {
-                "type": "git",
-                "url": "https://git.drupalcode.org/project/convert_entity_media_embed.git",
-                "reference": "1.0.0-alpha5"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://ftp.drupal.org/files/projects/convert_entity_media_embed-1.0.0-alpha5.zip",
-                "reference": "1.0.0-alpha5",
-                "shasum": "6373b7784d219d37151ef8e889f793c7b747fec3"
-            },
-            "require": {
-                "drupal/core": "^8.9 || ^9 || ^10"
-            },
-            "type": "drupal-module",
-            "extra": {
-                "drupal": {
-                    "version": "1.0.0-alpha5",
-                    "datestamp": "1699363463",
-                    "security-coverage": {
-                        "status": "not-covered",
-                        "message": "Project has not opted into security advisory coverage!"
-                    }
-                }
-            },
-            "installation-source": "dist",
-            "notification-url": "https://packages.drupal.org/8/downloads",
-            "license": [
-                "GPL-2.0-or-later"
-            ],
-            "authors": [
-                {
-                    "name": "eelkeblok",
-                    "homepage": "https://www.drupal.org/user/423078"
-                }
-            ],
-            "description": "Convert contrib entity embed tags to core media embed tags.",
-            "homepage": "https://www.drupal.org/project/convert_entity_media_embed",
-            "support": {
-                "source": "https://git.drupalcode.org/project/convert_entity_media_embed"
-            },
-            "install-path": "../../web/modules/convert_entity_media_embed"
-        },
         {
             "name": "drupal/core",
             "version": "10.1.7",