[ci] Optimizing pipeline (#5001)

* [DO NOT MERGE] Optimizing pipeline

* add stages

* remove lock for tests

* return locked

* empty commit for pipeline rerun

* add comment about DAG

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

* Update .gitlab-ci.yml

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

Co-authored-by: Denis Pisarev <17856421+TriplEight@users.noreply.github.com>

polkadot/scripts/gitlab/test_linux_stable.sh

-#!/usr/bin/env bash
-set -eux
-
-#shellcheck source=../common/lib.sh
-source "$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )/../common/lib.sh"
-
-# Builds with the runtime benchmarks/metrics features are only to be used for testing.
-time cargo test --workspace --profile testnet --verbose --locked --features=runtime-benchmarks,runtime-metrics
-
-# We need to separately run the `polkadot-node-metrics` tests. More specifically, because the 
-# `runtime_can_publish_metrics` test uses the `test-runtime` which doesn't support
-# the `runtime-benchmarks` feature.
-time cargo test  --profile testnet --verbose --locked --features=runtime-metrics -p polkadot-node-metrics