test: Fix hot restart test under --runs_per_test (#2609)
test: Fix hot restart test under --runs_per_test (#2609)

Description:
When using --runs_per_test with concurrency the individual invocations
of the hot restart test may collide. Bazel provides an environment
variable when using --runs_per_test that allows us to set --base_id in
each parallel invocation to a guaranteed unique value so this doesn't
happen.

Risk Level: Low

Testing: bazel test //test/integration:hotrestart_test --runs_per_test=100

Signed-off-by: e93d4ee3f9de1625d5809762ac3828138d402de6@google.com
istio/envoy,sebrandon1/envoy,dnoe/envoy,eklitzke/envoy,envoyproxy/envoy,eklitzke/envoy,envoyproxy/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,envoyproxy/envoy,envoyproxy/envoy,craffert0/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,jrajahalme/envoy,istio/envoy,lyft/envoy,lizan/envoy,jrajahalme/envoy,eklitzke/envoy,envoyproxy/envoy-wasm,lyft/envoy,istio/envoy,eklitzke/envoy,envoyproxy/envoy,istio/envoy,envoyproxy/envoy-wasm,lyft/envoy,jrajahalme/envoy,craffert0/envoy,lyft/envoy,dnoe/envoy,lyft/envoy,jrajahalme/envoy,sebrandon1/envoy,istio/envoy,envoyproxy/envoy,istio/envoy,sebrandon1/envoy,eklitzke/envoy,lyft/envoy,jrajahalme/envoy,sebrandon1/envoy,istio/envoy,lizan/envoy,lizan/envoy,craffert0/envoy,jrajahalme/envoy,envoyproxy/envoy,lizan/envoy,dnoe/envoy,eklitzke/envoy,craffert0/envoy,envoyproxy/envoy-wasm,envoyproxy/envoy,envoyproxy/envoy,sebrandon1/envoy,lizan/envoy,lizan/envoy,dnoe/envoy,envoyproxy/envoy-wasm,dnoe/envoy