feat(tests): enhance test coverage, add mainnet test for eip-2780

[LouisTsai-Csie]

Description

Add more EIP-2780 test coverage, and mainnet test cases.

New coverage:

• test_intrinsic_charges_authority_in_access_list
• test_self_transfer_with_delegated_sender
• test_intrinsic_decomposition_across_tx_types

The mainnet test cases are duplicated as tests already in this directory, and
cover less than the originals do:

test_eip_mainnet.py	Duplicates	Evidence
test_transaction_gas, all 10	test_value_moving_transactions, all 10	Same parametrization, identical gas per case; the original also asserts the EIP-7708 transfer log
test_contract_creation_gas, both	test_value_contract_creation_tx[success-*]	Both fill at 185,130; the original also covers init_reverts
test_authorization_gas[existing_authority]	test_single_authorization_charges[sets_new_delegation], test_account_write_first_write_of_authority[existing_eoa]	All three at 66,006
test_authorization_gas[new_authority]	test_single_authorization_charges[creates_account], test_account_write_first_write_of_authority[non_existent]	All three at 249,606

I am consider removing test_eip_mainnet.py and marking those existing tests with the mainnet marker instead.

Related Issues or PRs

issue #1940, #3217

Checklist

• Ran fast static checks to avoid CI fails, see Code Standards & Verifying Changes: just static
• PR title has the form <type>(<area>): <title>, where <type> and <area> come from an appropriate C-<type>, respectively A-<area>, label. The title should match the target squash commit message.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.42%. Comparing base (af13747) to head (356b1bb).
⚠️ Report is 6 commits behind head on forks/amsterdam.

Additional details and impacted files

@@               Coverage Diff                @@
##           forks/amsterdam    #3266   +/-   ##
================================================
  Coverage            93.42%   93.42%           
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  Files                  625      625           
  Lines                37032    37032           
  Branches              3385     3385           
================================================
  Hits                 34597    34597           
  Misses                1666     1666           
  Partials               769      769           

Flag	Coverage Δ
unittests	93.42% <ø> (ø)

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