Add protobuf and dashapi to sonic-mgmt (sonic-net#15743)

#### Why I did it
The testcases in sonic-mgmt need the packages of protobuf and dashapi

##### Work item tracking
- Microsoft ADO **(number only)**:

#### How I did it
Because the docker of sonic-mgmt is based on ubuntu20.04, it cannot directly install the packages compiled by slave due to dependency issues. Download related packaged directly from Azp.

#### How to verify it
Check azp stats.

dockers/docker-sonic-mgmt/Dockerfile.j2

@@ -210,6 +210,27 @@ RUN dpkg -i \
 debs/{{ deb }}{{' '}}
 {%- endfor %}
 
+# Install protobuf 3.21.12
+RUN mkdir -p /tmp/protobuf \
+    cd /tmp/protobuf \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/libprotobuf-dev_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/libprotobuf-lite32_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/libprotobuf32_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/libprotoc-dev_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/libprotoc32_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/protobuf-compiler_3.21.12-3_amd64.deb \
+    && wget https://sonicstorage.blob.core.windows.net/public/ubuntu/20.04/python3-protobuf_3.21.12-3_amd64.deb \
+    && dpkg -i *.deb \
+    && rm -rf /tmp/protobuf
+
+# Install dash-api
+RUN cd /tmp \
+    && mkdir -p /usr/lib/python3/dist-packages/dash_api \
+    && wget https://raw.githubusercontent.com/sonic-net/sonic-buildimage/master/src/sonic-dash-api/pypkg/__init__.py -O /usr/lib/python3/dist-packages/dash_api/__init__.py \
+    && git clone https://github.com/sonic-net/sonic-dash-api.git \
+    && protoc -I=sonic-dash-api/proto --python_out=/usr/lib/python3/dist-packages/dash_api sonic-dash-api/proto/*.proto \
+    && rm -rf /tmp/sonic-dash-api
+
 RUN mkdir /var/run/sshd
 EXPOSE 22
 

rules/sonic-dash-api.mk

@@ -6,7 +6,7 @@ LIB_SONIC_DASH_API = libdashapi_$(LIB_SONIC_DASH_API_VERSION)_$(CONFIGURED_ARCH)
 $(LIB_SONIC_DASH_API)_SRC_PATH = $(SRC_PATH)/sonic-dash-api
 
 $(LIB_SONIC_DASH_API)_DEPENDS += $(PROTOBUF) $(PROTOBUF_LITE) $(PROTOBUF_DEV) $(PROTOBUF_COMPILER)
-$(LIB_SONIC_DASH_API)_RDEPENDS += $(LIBSWSSCOMMON) $(LIBNL3) $(LIBNL_GENL3) $(LIBNL_ROUTE3) $(PROTOBUF) $(PROTOBUF_LITE) 
+$(LIB_SONIC_DASH_API)_RDEPENDS += $(PROTOBUF) $(PROTOBUF_LITE) $(PYTHON3_PROTOBUF)
 
 SONIC_DPKG_DEBS += $(LIB_SONIC_DASH_API)
 

slave.mk

@@ -1560,4 +1560,4 @@ jessie : $$(addprefix $(TARGET_PATH)/,$$(JESSIE_DOCKER_IMAGES)) \
 
 ## To build some commonly used libs. Some submodules depend on these libs.
 ## It is used in component pipelines. For example: swss needs libnl, libyang
-lib-packages: $(addprefix $(DEBS_PATH)/,$(LIBNL3) $(LIBYANG))
+lib-packages: $(addprefix $(DEBS_PATH)/,$(LIBNL3) $(LIBYANG) $(PROTOBUF) $(LIB_SONIC_DASH_API))