Remove miner codepath

[gakonst]

Supersedes #875.

Features:

• reverts the miner back to geth 1.9.10 code, makes code panic on miner calls

• introduces a new consensus engine which just passes blocks through

• makes the sync service write transactions & receipts directly to the database

• geth unit tests: fixed to provide enough gas & sign on transactions before submitting them

• integration tests

• being able to sync a replica (manually tested)

Fixes OP-285

[changeset-bot]

🦋 Changeset detected

Latest commit: 787f2ce

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@eth-optimism/l2geth	Patch

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[codecov-commenter]

Codecov Report

Merging #1077 (8cb6e17) into develop (6d7b12b) will not change coverage.
The diff coverage is n/a.

❗ Current head 8cb6e17 differs from pull request most recent head 787f2ce. Consider uploading reports for the commit 787f2ce to get more accurate results

@@           Coverage Diff            @@
##           develop    #1077   +/-   ##
========================================
  Coverage    82.26%   82.26%           
========================================
  Files           49       49           
  Lines         1900     1900           
  Branches       303      303           
========================================
  Hits          1563     1563           
  Misses         337      337           

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[smartcontracts]

Going to close this PR. We haven't had any movement on it for a while and we're likely going to need to completely redo it against the experimental branch.

[gakonst]

SGTM. Apologies for not being able to get it over the line at the time.