Add state attribute translations for device trackers (#89810)

homeassistant/components/device_tracker/strings.json

@@ -15,6 +15,29 @@
       "state": {
         "home": "[%key:common::state::home%]",
         "not_home": "[%key:common::state::not_home%]"
+      },
+      "state_attributes": {
+        "battery": {
+          "name": "Battery"
+        },
+        "gps_accuracy": {
+          "name": "GPS accuracy"
+        },
+        "latitude": {
+          "name": "Latitude"
+        },
+        "longitude": {
+          "name": "Longitude"
+        },
+        "source_type": {
+          "name": "Source",
+          "state": {
+            "bluetooth_le": "Bluetooth LE",
+            "bluetooth": "Bluetooth",
+            "gps": "GPS",
+            "router": "Router"
+          }
+        }
       }
     }
   }