fix(): Deleted default sales channel should be prevented (#10193)

FIXES CMRC-722

**What**
- It should not be allowed to delete a default sales channel
- The admin does not allow to delete a sales channel use as the default for the store

.changeset/honest-cars-knock.md

@@ -0,0 +1,7 @@
+---
+"@medusajs/core-flows": patch
+"@medusajs/types": patch
+"@medusajs/dashboard": patch
+---
+
+fix(): Deleted default sales channel should be prevented