ci: enable bazel remote caching on CircleCI (#21784)

This should cause Bazel builds to be incremental, only re-building parts of Angular affected by changes since the last build.
It also fixes a potential version skew, where CI was running the Bazel linter binaries in the ngcontainer docker image, but developers built them using the versions in WORKSPACE

PR Close #21784

.circleci/setup_cache.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Install bazel remote cache proxy
+# This is temporary until the feature is no longer experimental on CircleCI.
+# See remote cache documentation in /docs/BAZEL.md
+
+set -u -e
+
+readonly DOWNLOAD_URL="https://5-116431813-gh.circle-artifacts.com/0/pkg/bazel-remote-proxy-$(uname -s)_$(uname -m)"
+
+curl --fail -o ~/bazel-remote-proxy "$DOWNLOAD_URL"
+chmod +x ~/bazel-remote-proxy