FIXES PLT-6648 Add support for Server Side Encryption on S3 (#6467)

Help from Jason Blais on wording
Update storage_settings.jsx
Update en.json

webapp/i18n/en.json

@@ -466,6 +466,9 @@
   "admin.image.amazonS3SSLDescription": "When false, allow insecure connections to Amazon S3. Defaults to secure connections only.",
   "admin.image.amazonS3SSLExample": "E.g.: \"true\"",
   "admin.image.amazonS3SSLTitle": "Enable Secure Amazon S3 Connections:",
+  "admin.image.amazonS3SSEDescription": "When true, encrypt files in Amazon S3 using server-side encryption with Amazon S3-managed keys. See <a href=\"https://about.mattermost.com/default-server-side-encryption\">documentation</a> to learn more.",
+  "admin.image.amazonS3SSEExample": "E.g.: \"false\"",
+  "admin.image.amazonS3SSETitle": "Enable Server-Side Encryption for Amazon S3:",
   "admin.image.amazonS3SecretDescription": "Obtain this credential from your Amazon EC2 administrator.",
   "admin.image.amazonS3SecretExample": "E.g.: \"jcuS8PuvcpGhpgHhlcpT1Mx42pnqMxQY\"",
   "admin.image.amazonS3SecretTitle": "Amazon S3 Secret Access Key:",