feat(concat delete iterator): prefetch for concat delete range iterator

[soundOfDestiny]

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What's changed and what's your intention?

background: #9517 (comment)
However, when read_options.ignore_range_tombstone == false, concat delete range iterator will usually request for SstableMeta of an SST earlier than SstableMeta of the same SST is requested for by concat iterator.
Therefore, in such situation, prefetching in ConcatDeleteRangeIterator is meaningful and prefetching in ConcatIterator is meaningless.

This PR makes ConcatDeleteRangeIterator prefetch one extra SSTableMeta every time it requests for an SSTableMeta.

This PR maintains a prefetch queue (prefetched_metas: VecDeque) for SSTableMetas that have already been prefetched.

Checklist For Contributors

• I have demonstrated that backward compatibility is not broken by breaking changes and created issues to track deprecated features to be removed in the future. (Please refer to the issue)
• All checks passed in ./risedev check (or alias, ./risedev c)

Checklist For Reviewers

• I have requested macro/micro-benchmarks as this PR can affect performance substantially, and the results are shown.

Documentation

• My PR DOES NOT contain user-facing changes.

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Release note

[codecov]

Codecov Report

Merging #9693 (573bb5e) into main (0ff65d1) will decrease coverage by 0.03%.
The diff coverage is 30.23%.

@@            Coverage Diff             @@
##             main    #9693      +/-   ##
==========================================
- Coverage   70.97%   70.95%   -0.03%     
==========================================
  Files        1241     1241              
  Lines      207703   207826     +123     
==========================================
+ Hits       147412   147453      +41     
- Misses      60291    60373      +82     

Flag	Coverage Δ
rust	70.95% <30.23%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...rage/src/hummock/iterator/delete_range_iterator.rs	79.76% <0.00%> (-2.96%)	⬇️
...c/hummock/iterator/concat_delete_range_iterator.rs	64.94% <24.74%> (-20.34%)	⬇️
src/storage/src/hummock/sstable_store.rs	67.66% <60.00%> (-0.53%)	⬇️

... and 8 files with indirect coverage changes

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[soundOfDestiny]

#9517 (comment)