chore: rust ci tests with full backtraces enabled (hyperlane-xyz#3564)

### Description

Currently there's no way to know exactly where a panic occurred in rust
e2e. This adds full backtraces to show where the task `.join` that
caused the panic was. For example, this line isn't visible in the
regular backtrace and it shows that the panic happened when spawning the
anvil task (if you check out commit
`0cc48e164379d08a8f4c3703eaab79bb86e271d6`):
```
at [...]/hyperlane-monorepo/rust/utils/run-locally/src/main.rs:321:22
```

### Drive-by changes

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Are there any minor or drive-by changes also included?
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### Related issues

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- Fixes #[issue number here]
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### Backward compatibility

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implications, e.g. changes that would prohibit deploying older commits
using this infra tooling?

Yes/No
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### Testing

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What kind of testing have these changes undergone?

None/Manual/Unit Tests
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.github/workflows/test.yml

@@ -200,7 +200,7 @@ jobs:
         if: matrix.e2e-type == 'cosmwasm'
         working-directory: ./rust
         env:
-          RUST_BACKTRACE: 1
+          RUST_BACKTRACE: 'full'
 
       - name: agent tests excluding CosmWasm
         run: cargo run --release --bin run-locally
@@ -210,6 +210,7 @@ jobs:
           E2E_CI_MODE: 'true'
           E2E_CI_TIMEOUT_SEC: '600'
           E2E_KATHY_MESSAGES: '20'
+          RUST_BACKTRACE: 'full'
 
   e2e:
     runs-on: ubuntu-latest