fix(dashboard): RMA allow shipping unset (#12021)

**What**
- allow unsetting shipping in RMA flows + bug cleanup around shipping flows in claims / exchanges
- additional fixes:
  - product type create form 
  - product type delete
  - delete confirmation messages
  - fix a few inventory strings + material field

---

CLOSES CMRC-945
CLOSES CMRC-953
CLOSES CMRC-967
CLOSES CMRC-963
CLOSES CMRC-954


Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/admin/dashboard/src/i18n/translations/$schema.json

@@ -3034,6 +3034,9 @@
         "manageLocations": {
           "type": "string"
         },
+        "manageLocationQuantity": {
+          "type": "string"
+        },
         "deleteWarning": {
           "type": "string"
         },
@@ -3252,6 +3255,7 @@
         "locationLevels",
         "associatedVariants",
         "manageLocations",
+        "manageLocationQuantity",
         "deleteWarning",
         "editItemDetails",
         "create",