Generate Unit Tests for Benchmarks (#5527)

* Update to latest staking

* generate tests for benchmarking

* add tests, fix warnings

* starting on democracy

* impl_benchmark_tests

* Way more readable

* add test feature flag (does this work?)

* Fix `successful_origin` impl

* democracry benchmark tests

* Fix example benchmarks, add tests

* identity benchmark tests

* Update im-online benchmark tests

* try to add session benchmarking tests (problem with mock)

* staking and timestamp

* add test for treasury, issue with dynamic contains

* utility

* Vesting

* test instead of check

* hide until we figure out what is wrong

* add docs

* close code

* Create custom mock for session-pallet-benchmarking

* Use refcell pattern

* make un-pub

* test-linux-stable includes `runtime-benchmarks` feature

* Revert "test-linux-stable includes `runtime-benchmarks` feature"

This reverts commit a2dab38abd18ac3eb8a6220e4a00e687740bd38c.

* run tests in `--release`

* undo balance change

* build wasm

substrate/.gitlab-ci.yml

@@ -287,7 +287,7 @@ test-runtime-benchmarks:
       - $DEPLOY_TAG
   script:
     - cd bin/node/cli
-    - BUILD_DUMMY_WASM_BINARY=1 time cargo check --verbose --features runtime-benchmarks
+    - WASM_BUILD_NO_COLOR=1 time cargo test --release --verbose --features runtime-benchmarks
     - sccache -s
 
 test-linux-stable-int: