Adjustments to syntax

spezi-invitation-code/README.md

@@ -12,6 +12,7 @@ SPDX-License-Identifier: MIT
 
 Our Firestore instance also contains a collection called `invitationCodes` with a fixed set of secret, randomly generated codes. During onboarding, we sign the user in anonymously so we can check if they have a valid code. If they do, we assign that code to their new de-anonymized account and remove it from `invitationCodes` so it cannot be used again. This system is designed to hedge against spam and unapproved use.
 
+```mermaid
 graph TD
     start["Welcome Screen(s)"]
     in1["Invitation Code View"]
@@ -36,6 +37,7 @@ graph TD
     credentials --> credvalidation
     credvalidation -->|No| login
     credvalidation -->|Yes| home
+```
 
 Anytime someone tries to sign up for an account, a blocking cloud function will automatically be triggered, denying sign-up access to users who enter invalid invitation codes.
 Since the Firebase instance is set up only to accept authenticated requests, this system eliminates the ability for anyone without an invitation code to send samples to our servers.