Remove unused sort for segmenta meta list

[k-yomo]

https://github.com/quickwit-inc/tantivy/blob/02174d26af50af2cf8b9f7592c35e90aae14de70/src/indexer/segment_updater.rs#L415-L423

The segment_metas method is only used in the above method, but it's re-sorted by doc count in the method as following. So the original sort by segment id can be removed to make it little more efficient.
https://github.com/quickwit-inc/tantivy/blob/02174d26af50af2cf8b9f7592c35e90aae14de70/src/indexer/segment_updater.rs#L438

[codecov-commenter]

Codecov Report

Merging #1218 (6f4186c) into main (02174d2) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1218      +/-   ##
==========================================
+ Coverage   94.05%   94.09%   +0.03%     
==========================================
  Files         205      205              
  Lines       34514    34517       +3     
==========================================
+ Hits        32463    32478      +15     
+ Misses       2051     2039      -12     

Impacted Files	Coverage Δ
src/indexer/segment_register.rs	84.84% <100.00%> (-0.45%)	⬇️
src/postings/mod.rs	98.57% <100.00%> (+0.22%)	⬆️
src/core/segment_id.rs	64.00% <0.00%> (-12.00%)	⬇️
src/fastfield/reader.rs	94.06% <0.00%> (-0.85%)	⬇️
src/schema/schema.rs	98.40% <0.00%> (-0.19%)	⬇️
src/functional_test.rs	0.00% <0.00%> (ø)
src/positions/reader.rs	100.00% <0.00%> (ø)
src/tokenizer/ascii_folding_filter.rs	99.92% <0.00%> (+0.07%)	⬆️
query-grammar/src/query_grammar.rs	99.64% <0.00%> (+0.35%)	⬆️
... and 12 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 02174d2...6f4186c. Read the comment docs.

[fulmicoton]

LGTM Thank you @k-yomo. The explanation were very helpful too. I am waiting for the CI and will merge after.