Use native type, remove lots of type conversions

[abeobk]

Check List:

• [x] Tests pass (./test.sh <username> shows no differences between expected and actual outputs)
• [x] All formatting changes by the build are committed
• [x] Your launch script is named calculate_average_<username>.sh (make sure to match casing of your GH user name) and is executable
• [x] Output matches that of calculate_average_baseline.sh
• [x] For new entries, or after substantial changes: When implementing custom hash structures, please point to where you deal with hash collisions (line number)

STANDARD Benchmark 1: ./calculate_average_abeobk.sh Time (mean ± σ): 560.5 ms ± 2.9 ms [User: 2.6 ms, System: 1.6 ms] Range (min … max): 557.2 ms … 567.1 ms 10 runs

10K STATION Benchmark 1: ./calculate_average_abeobk.sh Time (mean ± σ): 2.100 s ± 0.007 s [User: 0.002 s, System: 0.003 s] Range (min … max): 2.089 s … 2.108 s 10 runs

[gunnarmorling]

00:02.091 now, nice!

Benchmark 1: timeout -v 300 ./calculate_average_abeobk.sh 2>&1
  Time (mean ± σ):      2.087 s ±  0.014 s    [User: 0.002 s, System: 0.004 s]
  Range (min … max):    2.063 s …  2.099 s    5 runs

Summary
  abeobk: trimmed mean 2.09120156588, raw times 2.06283919988,2.08849347488,2.09662411088,2.08848711188,2.09894213488

Leaderboard

| # | Result (m:s.ms) | Implementation     | JDK | Submitter     | Notes     |
|---|-----------------|--------------------|-----|---------------|-----------|
|   | 00:02.091 | [link](https://github.com/gunnarmorling/1brc/blob/main/src/main/java/dev/morling/onebrc/CalculateAverage_abeobk.java)| 21.0.2-graal | [Van Phu DO](https://github.com/abeobk) | GraalVM native binary, uses Unsafe |