test: enable/improve rpc tests

[federico-stacks]

Description

This patch does some work along rpc unit tests:

• For postblock_proposal tests:
  • Remove ignore tag from some tests to make them run automatically as aprt of unit tests automation
  • Make a stale (ignored) test work again: test_block_proposal_validation_timeout
  • add test coverage for a missing scenario: test_block_proposal_validation_execution_time_expired_blames_tx
  • Removed test entry net::api::tests::postblock_proposal::test_try_make_response from tests-p2p.yml workflow as it is already run as part of our unit tests automation
• For getmapentry tests:
  • removed 3 commented-out tests
  • improve scenarios coverage in the already existing test case: test_try_make_response

Applicable issues

• fixes tests: some RPC tests are no executed by CI #7350

Additional info (benefits, drawbacks, caveats)

Checklist

• Test coverage for new or modified code paths
• For new Clarity features or consensus changes, add property tests (see docs/property-testing.md)
• Changelog fragment(s) or "no changelog" label added (see changelog.d/README.md)
• Required documentation changes (e.g., rpc/openapi.yaml for RPC endpoints, event-dispatcher.md for new events)
• New clarity functions have corresponding PR in clarity-benchmarking repo

[coveralls]

Coverage Report for CI Build 29428937263

Coverage increased (+0.8%) to 86.522%

Details

• Coverage increased (+0.8%) from the base build.
• Patch coverage: No coverable lines changed in this PR.
• 11991 coverage regressions across 163 files.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

11991 previously-covered lines in 163 files lost coverage.

Top 10 Files by Coverage Loss	Lines Losing Coverage	Coverage
stackslib/src/chainstate/burn/db/sortdb.rs	638	90.43%
stackslib/src/chainstate/stacks/db/blocks.rs	528	89.93%
stackslib/src/chainstate/nakamoto/mod.rs	488	84.91%
stackslib/src/config/mod.rs	324	78.53%
stackslib/src/net/relay.rs	324	74.43%
stackslib/src/net/mod.rs	312	78.18%
stackslib/src/chainstate/stacks/index/storage.rs	277	82.41%
clarity/src/vm/database/clarity_db.rs	273	82.02%
stackslib/src/chainstate/stacks/db/transactions.rs	269	97.13%
stackslib/src/chainstate/stacks/miner.rs	266	83.18%

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Coverage Stats

Relevant Lines:	231325
Covered Lines:	200147
Line Coverage:	86.52%
Coverage Strength:	19568062.29 hits per line

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💛 - Coveralls

[rob-stacks]

LGTM

[federico-stacks]

I had to update to latest merge to avoid a conflict materialized on the merge queue