feat: add --gas flag to ape test command to output gas reports after tests

[antazoey]

What I did

fixes: #350

How I did it

• Add --gas flag to ape test command
• In function isolation fixture, build the tree on each incoming receipt
• In terminal reporting pytest hook, output the gas report

How to verify it

1. Make sure to use a provider like ape-hardhat or ape-foundry that supports tracing.
2. Go to your project with tests
3. Run ape test --gas or however you run your tests, just include --gas.

Checklist

• All changes are completed
• New test cases have been added
• Documentation has been updated

[antazoey]

• Fix regression in trace output (failing in hardhat tests)

[antazoey]

Tests: ApeWorX/ape-hardhat#98

[antazoey]

• Fix issue found in testing where we would get duplicate stats in the gas report (same call entered twice, thus corrupting the stats)

[antazoey]

• Fix issue where sessional and module-scoped fixtures containing receipts don't show up in gas report