BUG: future.tests::check(plan = "sequential", tags = "options") tests fail if called more than once

# Issue

The `future() - preserve R options` tests fail in interacive mode, _if called more than once_.

```r
> results <- future.tests::check(plan = "sequential", tags = "options")
── Settings ─────────────────────────────────────────────────────────────────────────────────────────────
- future.tests version : 0.5.0
- R_FUTURE_TESTS_ROOT :
- Option 'future.tests.root': NULL
- Default test set folder : /home/hb/R/x86_64-pc-linux-gnu-library/4.2-CBI-gcc9/future.tests/test-db
- Max number of workers : 2
- Timeout : N/A

── Running 2 test sets with plan(sequential) ────────────────────────────────────────────────────────────
ℹ Backend package: future 1.30.0.9014
✔ future() - preserve R options (1 test) (182ms)
✔ future() - preserve R options (1 test) (107ms)

Number of tests: 2

Duration: 346ms

Results: 0 errors ✔ | 0 timeouts ✔
```

```r
> results <- future.tests::check(plan = "sequential", tags = "options")
── Settings ─────────────────────────────────────────────────────────────────────────────────────────────
- future.tests version : 0.5.0
- R_FUTURE_TESTS_ROOT :
- Option 'future.tests.root': NULL
- Default test set folder : /home/hb/R/x86_64-pc-linux-gnu-library/4.2-CBI-gcc9/future.tests/test-db
- Max number of workers : 2
- Timeout : N/A

── Running 2 test sets with plan(sequential) ────────────────────────────────────────────────────────────
ℹ Backend package: future 1.30.0.9014
✖ future() - preserve R options (1 test) (30ms)
✖ lazy=FALSE, globals=TRUE, stdout=TRUE
✖ future() - preserve R options (1 test) (10ms)
✖ lazy=FALSE, globals=TRUE, stdout=TRUE

Number of tests: 2

Duration: 77ms

Results: 2 errors ✖ | 0 timeouts ✔
```