fix(create-medusa-app): --db-url keep asking db credentials (#11037)

* fix create-medusa-app db-url error

* removed empty lines

* changeset

.changeset/chatty-badgers-visit.md

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+---
+"create-medusa-app": patch
+---
+
+Fix issue where create-medusa-app repeatedly asked for database credentials even when --db-url was specified. The logic in MedusaProjectCreator->create()->initializeProject()->setupDatabase() always defines a dbName. Updated the getDbClientAndCredentials() method to check db-url first