miner, consensus, core: remove tracing in mining workflow

[manav2401]

Description

This PR removes open telemetry based tracing from the whole mining workflow. The tracing extended into consensus and core blockchain functions from miner is also removed in this PR. We weren't checking the tracing from a long time and the way it was implemented increased the code complexity a lot. As a replacement to get observability in mining, we can add more logs and metrics as a separate task.

For mining related e2e tests, some functions were also modified in miner/test_backend.go to introduce artificial delays. The code was out of sync. This PR also brings it in sync with original miner/worker.go methods.

Changes

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)
• Changes only for a subset of nodes

Breaking changes

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Nodes audience

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Checklist

• I have added at least 2 reviewer or the whole pos-v1 team
• I have added sufficient documentation in code
• I will be resolving comments - if any - by pushing each fix in a separate commit and linking the commit hash in the comment reply
• Created a task in Jira and informed the team for implementation in Erigon client (if applicable)
• Includes RPC methods changes, and the Notion documentation has been updated

Cross repository changes

• This PR requires changes to heimdall
  • In case link the PR here:
• This PR requires changes to matic-cli
  • In case link the PR here:

Testing

• I have added unit tests
• I have added tests to CI
• I have tested this code manually on local environment
• I have tested this code manually on remote devnet using express-cli
• I have tested this code manually on mumbai/amoy
• I have created new e2e tests into express-cli

Manual tests

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Additional comments

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