Benchmarking fixes

[4meta5]

• Closes Replace all manual weight accounting with benchmark-derived functions #1190
• Closes Verify expected state changes for non-extrinsic benchmarks #1227
• Closes Bound DKG timeouts per block in pallet-shards::on-initialize #1228

Changes

Manual => Derived Weights:

• elections::try_elect_shard
• shards::do_dkg_timeout
• members::do_heartbeat_timeouts

No longer need to return Weights:

• shards::member_offline
• elections::member_offline
• members::member_offline

Verify checks added:

• shards::do_dkg_timeout
• members::do_heartbeat_timeouts
• elections::try_elect_shard
• tasks::prepare_batches
• tasks::schedule_tasks

Verify checks failed => new worst-case:

• elections::try_elect_shard
• tasks::schedule_tasks
• tasks::prepare_batches
• tasks::submit_task_result

Before merging:

• re-run benchmarks => update weights

Upper bounds:

• MaxTasksPerBlock = 50 (max measured by runtime test was 81)
• MaxBatchesPerBlock = 10 (max measured by runtime test was 41)
• shards::Config::MaxTimeoutsPerBlock = 100
• members::Config::MaxTimeoutsPerBlock = 100

Follow Ups

• Runtime tests to ensure sensible assignments for MaxTimeoutsPerBlock #1235
• Bound elections::on_initialize #1234

[dvc94ch]

lgtm! thanks @4meta5

[dvc94ch]

ci is failing do to some assertions being triggered...

[4meta5]

ci is failing do to some assertions being triggered...

yes currently debugging the failed assertions, progress tracked in PR description

will not merge until weights are updated and CI is green