PREF: Speed up to_set

[Zeroto521]

• closes PERF: to_set speeds up especial to large data #543
• whatsnew entry

test via timeit command

s =	loop ranges	set(s)	set(s.values)	set(s.to_numpy())	set(s.to_list())	set(s.unique())
pd.Series(range(10))	7e4 ~ 7e6	2.36 µs ± 70.2 ns	2.42 µs ± 123 ns	3.45 µs ± 82.7 ns	999 ns ± 18.2 ns	27.4 µs ± 771 ns
pd.Series(list(range(10))*1e4)	7e2 ~ 7e3	8.33 ms ± 665 µs	6.46 ms ± 198 µs	6.75 ms ± 500 µs	1.75 ms ± 23.7 µs	952 µs ± 8.71 µs
pd.Series(range(int(1e5)))	7e2	13.7 ms ± 469 µs	9.95 ms ± 472 µs	9.77 ms ± 649 µs	6.3 ms ± 328 µs	12.7 ms ± 820 µs

[codecov]

Codecov Report

Merging #585 (98d8701) into main (055b3f5) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #585   +/-   ##
=======================================
  Coverage   99.55%   99.55%           
=======================================
  Files          75       75           
  Lines         903      903           
  Branches       99       99           
=======================================
  Hits          899      899           
  Misses          1        1           
  Partials        3        3           

Impacted Files	Coverage Δ
dtoolkit/accessor/index/to_set.py	100.00% <ø> (ø)
dtoolkit/accessor/series/to_set.py	100.00% <100.00%> (ø)

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