feat: update vue-letter and allow transform css (#10865)

Emails from iOS and MacOS clients can often come with size
transformation. This results in a broken layout when sanitizing with Vue
letter.

This PR updates the vue-letter to include the [recent changes made
there](https://github.com/mat-sz/vue-letter/pull/2). And adds the
`transform` and `transform-origin` properties to the allow list

Ref: https://www.caniemail.com/features/css-transform/

---------

Co-authored-by: Muhsin Keloth <muhsinkeramam@gmail.com>

package.json

@@ -72,6 +72,7 @@
     "highlight.js": "^11.10.0",
     "idb": "^8.0.0",
     "js-cookie": "^3.0.5",
+    "lettersanitizer": "^1.0.6",
     "libphonenumber-js": "^1.11.9",
     "markdown-it": "^13.0.2",
     "markdown-it-link-attributes": "^4.0.1",
@@ -92,7 +93,7 @@
     "vue-datepicker-next": "^1.0.3",
     "vue-dompurify-html": "^5.1.0",
     "vue-i18n": "9.14.2",
-    "vue-letter": "^0.2.0",
+    "vue-letter": "^0.2.1",
     "vue-multiselect": "3.1.0",
     "vue-router": "~4.4.5",
     "vue-upload-component": "^3.1.17",