fix: panic if spawn when task drop with madsim

[MrCroxx]

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What's changed and what's your intention?

Temporarily disable file cache insert when memory cache eviction, because it may cause tokio spawn when task drop, which madsim cannot support for now.

FYI: madsim-rs/madsim#182
CI failure: https://buildkite.com/risingwavelabs/pull-request/builds/35387#018bcd05-4da3-488f-839c-412e04b84180

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
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• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

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[Little-Wallace]

LGTM

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

Comparison is base (cde91a0) 67.86% compared to head (b092861) 67.87%.

Files	Patch %	Lines
src/storage/src/hummock/sstable_store.rs	50.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #13417      +/-   ##
==========================================
+ Coverage   67.86%   67.87%   +0.01%     
==========================================
  Files        1526     1526              
  Lines      260047   260053       +6     
==========================================
+ Hits       176468   176508      +40     
+ Misses      83579    83545      -34     

Flag	Coverage Δ
rust	67.87% <50.00%> (+0.01%)	⬆️

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