[fix](ngram bloomfilter) fix narrow conversion for ngram bf_size

[airborne12]

What problem does this PR solve?

Problem Summary:
Fix ngram bloomfilter index coredump as below

*** SIGFPE integer divide by zero (@0x56294f026472) received by PID 4016941 (TID 4019213 OR 0x7f294eb4d640) from PID 1325556850; stack trace: ***
 0# doris::signal::(anonymous namespace)::FailureSignalHandler(int, siginfo_t*, void*) at be/src/common/signal_handler.h:421
 1# PosixSignals::chained_handler(int, siginfo*, void*) [clone .part.0] in bin/jdk-17.0.2/lib/server/libjvm.so
 2# JVM_handle_linux_signal in bin/jdk-17.0.2/lib/server/libjvm.so
 3# 0x00007F3071042520 in /lib/x86_64-linux-gnu/libc.so.6
 4# doris::segment_v2::NGramBloomFilter::add_bytes(char const*, unsigned int) at be/src/olap/rowset/segment_v2/ngram_bloom_filter.cpp:61
 5# doris::ITokenExtractorHelper<doris::NgramTokenExtractor>::string_to_bloom_filter(char const*, unsigned long, doris::segment_v2::BloomFilter&) const at be/src/olap/itoken_extractor.h:61
 6# doris::segment_v2::NGramBloomFilterIndexWriterImpl::add_values(void const*, unsigned long) at be/src/olap/rowset/segment_v2/bloom_filter_index_writer.cpp:250

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[doris-robot]

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Please clearly describe your PR:

1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
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[airborne12]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[doris-robot]

TeamCity be ut coverage result:
Function Coverage: 37.90% (9864/26026)
Line Coverage: 29.07% (82064/282344)
Region Coverage: 28.28% (42260/149434)
Branch Coverage: 24.86% (21439/86250)
Coverage Report: http://coverage.selectdb-in.cc/coverage/58d386df8a7122e86d2f8f74205e088a19096de4_58d386df8a7122e86d2f8f74205e088a19096de4/report/index.html

[airborne12]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.

[airborne12]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[qidaye]

LGTM

[github-actions]

PR approved by at least one committer and no changes requested.

[csun5285]

LGTM

[doris-robot]

TeamCity be ut coverage result:
Function Coverage: 37.79% (9846/26054)
Line Coverage: 29.08% (82367/283227)
Region Coverage: 28.19% (42325/150148)
Branch Coverage: 24.77% (21455/86620)
Coverage Report: http://coverage.selectdb-in.cc/coverage/9497e00f2c31ee9220b730f3c762b925a9567f52_9497e00f2c31ee9220b730f3c762b925a9567f52/report/index.html

[eldenmoon]

LGTM