[ci] Remove saiserverv2 build in official build. (#15191)

Why I did it
libsaithriftv2 build fails and nobody is maintaining saiserverv2's build.
Remove them from official build.

Work item tracking
Microsoft ADO (number only): 23764652
How I did it
How to verify it

Author: liushilongbuaa

.azure-pipelines/azure-pipelines-build.yml

@@ -159,16 +159,6 @@ jobs:
                 pushd ./src/sonic-sairedis/SAI
                 git stash
                 popd 
-                make $BUILD_OPTIONS ENABLE_SYNCD_RPC=y SAITHRIFT_V2=y target/docker-saiserverv2-brcm.gz
-                pushd ./src/sonic-sairedis/SAI
-                git stash
-                popd
-              fi
-              if [ $(GROUP_NAME) == barefoot ]; then
-                make $BUILD_OPTIONS SAITHRIFT_V2=y ENABLE_SYNCD_RPC=y target/docker-saiserverv2-bfn.gz
-                pushd ./src/sonic-sairedis/SAI
-                git stash
-                popd
               fi
             fi
             if [ $(syncd_rpc_image) == yes ]; then