Updated website docs and /twenty-server/.env (#8801)

Fix for the issue Incorrect Database Connection String in .env File
#8741

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Co-authored-by: Félix Malfait <felix@twenty.com>

packages/twenty-server/.env.test

@@ -1,4 +1,4 @@
-PG_DATABASE_URL=postgres://postgres:twenty@localhost:5432/test
+PG_DATABASE_URL=postgres://postgres:postgres@localhost:5432/test
 REDIS_URL=redis://localhost:6379
 
 DEBUG_MODE=true