[submodule] Update submodule sonic-dash-ha to the latest HEAD automatically (#25551)

#### Why I did it
src/sonic-dash-ha
```
* a6cf697 - (HEAD -> master, origin/master, origin/HEAD) update dash-api submodule (3 hours ago) [Jing Zhang]
* 64022eb - Change convert_pb_to_json to parse proto encoded value from binary input (#142) (9 hours ago) [yue-fred-gao]
* 53fb250 - [ci] fix build error and save binaries (#144) (28 hours ago) [Jing Zhang]
```
#### How I did it
#### How to verify it
#### Description for the changelog

Author: mssonicbld