Merge pull request #5816 from kata-containers/protoc

CI: Install protobuf-compiler in the ci environment

Author: ChengyuZhu6

.ci/jenkins_job_build.sh

@@ -231,6 +231,8 @@ run_unit_test() {
 		sudo -E INSTALL_IN_GOPATH=false ./ci/install_yq.sh
 		echo "Install clang"
 		sudo -E apt-get install -y clang
+		echo "Install protobuf-compiler"
+		sudo -E apt-get install -y protobuf-compiler
 		echo "Installing libseccomp library from sources"
 		libseccomp_install_dir=$(mktemp -d -t libseccomp.XXXXXXXXXX)
 		gperf_install_dir=$(mktemp -d -t gperf.XXXXXXXXXX)