buildscripts: drop xDS v2 interop test (#9783)

This disables xDS v2 support interop test.
xDS v2 support dropped in https://github.com/grpc/grpc-java/pull/9760.

Internal ref cl/499306755

buildscripts/kokoro/xds.cfg

@@ -1,11 +0,0 @@
-# Config file for internal CI
-
-# Location of the continuous shell script in repository.
-build_file: "grpc-java/buildscripts/kokoro/xds.sh"
-timeout_mins: 360
-action {
-  define_artifacts {
-    regex: "**/*sponge_log.*"
-    regex: "github/grpc/reports/**"
-  }
-}

buildscripts/kokoro/xds.sh

@@ -1,39 +0,0 @@
-#!/bin/bash
-
-set -exu -o pipefail
-if [[ -f /VERSION ]]; then
-  cat /VERSION
-fi
-
-cd github
-
-pushd grpc-java/interop-testing
-GRADLE_OPTS="-Dorg.gradle.jvmargs='-Xmx1g'" \
-  ../gradlew installDist -x test -PskipCodegen=true -PskipAndroid=true
-popd
-
-git clone -b master --single-branch --depth=1 https://github.com/grpc/grpc.git
-
-grpc/tools/run_tests/helper_scripts/prep_xds.sh
-
-# Test cases "path_matching" and "header_matching" are not included in "all",
-# because not all interop clients in all languages support these new tests.
-#
-# TODO(ericgribkoff): remove "path_matching" and "header_matching" from
-# --test_case after they are added into "all".
-JAVA_OPTS=-Djava.util.logging.config.file=grpc-java/buildscripts/xds_logging.properties \
-  python3 grpc/tools/run_tests/run_xds_tests.py \
-    --test_case="ping_pong,circuit_breaking" \
-    --project_id=grpc-testing \
-    --project_num=830293263384 \
-    --source_image=projects/grpc-testing/global/images/xds-test-server-5 \
-    --path_to_server_binary=/java_server/grpc-java/interop-testing/build/install/grpc-interop-testing/bin/xds-test-server \
-    --gcp_suffix=$(date '+%s') \
-    --verbose \
-    ${XDS_V3_OPT-} \
-    --client_cmd="grpc-java/interop-testing/build/install/grpc-interop-testing/bin/xds-test-client \
-      --server=xds:///{server_uri} \
-      --stats_port={stats_port} \
-      --qps={qps} \
-      {rpcs_to_send} \
-      {metadata_to_send}"

buildscripts/kokoro/xds_v3.sh

@@ -1,3 +1,34 @@
 #!/bin/bash
 
-XDS_V3_OPT="--xds_v3_support" `dirname $0`/xds.sh
+set -exu -o pipefail
+if [[ -f /VERSION ]]; then
+  cat /VERSION
+fi
+
+cd github
+
+pushd grpc-java/interop-testing
+GRADLE_OPTS="-Dorg.gradle.jvmargs='-Xmx1g'" \
+  ../gradlew installDist -x test -PskipCodegen=true -PskipAndroid=true
+popd
+
+git clone -b master --single-branch --depth=1 https://github.com/grpc/grpc.git
+
+grpc/tools/run_tests/helper_scripts/prep_xds.sh
+
+JAVA_OPTS=-Djava.util.logging.config.file=grpc-java/buildscripts/xds_logging.properties \
+  python3 grpc/tools/run_tests/run_xds_tests.py \
+    --test_case="ping_pong,circuit_breaking" \
+    --project_id=grpc-testing \
+    --project_num=830293263384 \
+    --source_image=projects/grpc-testing/global/images/xds-test-server-5 \
+    --path_to_server_binary=/java_server/grpc-java/interop-testing/build/install/grpc-interop-testing/bin/xds-test-server \
+    --gcp_suffix=$(date '+%s') \
+    --verbose \
+    --xds_v3_support \
+    --client_cmd="grpc-java/interop-testing/build/install/grpc-interop-testing/bin/xds-test-client \
+      --server=xds:///{server_uri} \
+      --stats_port={stats_port} \
+      --qps={qps} \
+      {rpcs_to_send} \
+      {metadata_to_send}"