fix bitmap new_trued

[codecov[bot]]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (6a4b531) 83.36% compared to head (7285bc1) 83.37%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1580 +/- ## ======================================= Coverage 83.36% 83.37% ======================================= Files 391 391 Lines 42982 42982 ======================================= + Hits 35834 35838 +4 + Misses 7148 7144 -4 ``` | [Files](https://app.codecov.io/gh/jorgecarleitao/arrow2/pull/1580?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Jorge+Leitao) | Coverage Δ | | |---|---|---| | [src/bitmap/immutable.rs](https://app.codecov.io/gh/jorgecarleitao/arrow2/pull/1580?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Jorge+Leitao#diff-c3JjL2JpdG1hcC9pbW11dGFibGUucnM=) | `86.69% <100.00%> (+4.72%)` | :arrow_up: | ... and [5 files with indirect coverage changes](https://app.codecov.io/gh/jorgecarleitao/arrow2/pull/1580/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Jorge+Leitao)

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