gvisor/bazel: use python2 to build runsc-debian

$ bazel build runsc:runsc-debian
  File ".../bazel_tools/tools/build_defs/pkg/make_deb.py", line 311,
  in GetFlagValue:
    flagvalue = flagvalue.decode('utf-8')
AttributeError: 'str' object has no attribute 'decode'

make_deb.py is incompatible with Python3.
https://github.com/bazelbuild/bazel/issues/8443

PiperOrigin-RevId: 253691923

Dockerfile

@@ -1,6 +1,6 @@
 FROM ubuntu:bionic
 
-RUN apt-get update && apt-get install -y curl gnupg2 git
+RUN apt-get update && apt-get install -y curl gnupg2 git python3
 RUN echo "deb [arch=amd64] http://storage.googleapis.com/bazel-apt stable jdk1.8" | tee /etc/apt/sources.list.d/bazel.list && \
 	curl https://bazel.build/bazel-release.pub.gpg | apt-key add -
 RUN apt-get update && apt-get install -y bazel && apt-get clean

runsc/BUILD

@@ -96,6 +96,11 @@ pkg_deb(
     maintainer = "The gVisor Authors <gvisor-dev@googlegroups.com>",
     package = "runsc",
     postinst = "debian/postinst.sh",
+    tags = [
+        # TODO(b/135475885): pkg_deb requires python2:
+        # https://github.com/bazelbuild/bazel/issues/8443
+        "manual",
+    ],
     version_file = ":version.txt",
     visibility = [
         "//visibility:public",

tools/run_tests.sh

@@ -92,6 +92,14 @@ build_everything() {
     "${BUILD_PACKAGES[@]}"
 }
 
+build_runsc_debian() {
+  cd ${WORKSPACE_DIR}
+
+  # TODO(b/135475885): pkg_deb is incompatible with Python3.
+  # https://github.com/bazelbuild/bazel/issues/8443
+  bazel build --host_force_python=py2 runsc:runsc-debian
+}
+
 # Run simple tests runs the tests that require no special setup or
 # configuration.
 run_simple_tests() {
@@ -277,6 +285,8 @@ main() {
   run_syscall_tests
   run_runsc_do_tests
 
+  build_runsc_debian
+
   # Build other flavors too.
   build_everything dbg