Use .db extension for SQLite configuration example (#5313)

dev/secrets.json.example

@@ -21,7 +21,7 @@
       "connectionString": "server=localhost;uid=root;pwd=SET_A_PASSWORD_HERE_123;database=vault_dev"
     },
     "sqlite": {
-      "connectionString": "Data Source=/path/to/bitwardenServer/repository/server/dev/db/bitwarden.sqlite"
+      "connectionString": "Data Source=/path/to/bitwardenServer/repository/server/dev/db/bitwarden.db"
     },
     "identityServer": {
       "certificateThumbprint": "<your Identity certificate thumbprint with no spaces>"