Lefant T700: make some dps optional

This almost matches with M210P, but some dps that are normally optional
in other vacuums are missing from the M210P log.  Assume this may be an
issue with matching this model as well.

Issue #1467

custom_components/tuya_local/devices/lefant_t700_vacuum.yaml

@@ -29,6 +29,7 @@ primary_entity:
           value: random
     - id: 4
       type: string
+      optional: true
       name: direction_control
       mapping:
         - dps_val: forward
@@ -61,6 +62,7 @@ primary_entity:
           value: spot_cleaning
     - id: 13
       type: boolean
+      optional: true
       name: locate
     - id: 15
       type: string