[MM-54770] Add ability to export profile pictures and fix importing them (#25042)

* add ability to export pp and fix import

* remove unused nopSeeker

* remove debug log

* fix shadow vars

* generate a warning instead of an error when unable to export profile picture

* fix merge conflicts

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Co-authored-by: Mattermost Build <build@mattermost.com>

server/i18n/en.json

@@ -4370,6 +4370,10 @@
     "id": "api.user.get_authorization_code.endpoint.app_error",
     "translation": "Error retrieving endpoint from Discovery Document."
   },
+  {
+    "id": "api.user.get_profile_image_path.app_error",
+    "translation": "Error while checking if a user has a custom profile image."
+  },
   {
     "id": "api.user.get_uploads_for_user.forbidden.app_error",
     "translation": "Failed to get uploads."