fix: Create character set only once

[noahsmartin]

We seem to be hitting a bug with character set, this won't completely avoid it but will reduce the chance of hitting it and will make the code a bit more efficient at the cost of storing one character set in memory

#skip-changelog

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
⚠️ Please upload report for BASE (main@83bb978). Learn more about missing BASE report.
⚠️ Report is 2 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff            @@
##             main     #5871   +/-   ##
========================================
  Coverage        ?   86.685%           
========================================
  Files           ?       423           
  Lines           ?     36614           
  Branches        ?     17347           
========================================
  Hits            ?     31739           
  Misses          ?      4829           
  Partials        ?        46           

Files with missing lines	Coverage Δ
...Swift/Core/Helper/SentryBaggageSerialization.swift	100.000% <100.000%> (ø)

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[philipphofmann]

LGTM, if this fixes something as pointed out in Slack, I believe we should add a changelog entry and prefix the PR title with fix: .

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1228.90 ms	1244.33 ms	15.43 ms
Size	23.75 KiB	920.56 KiB	896.82 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
ebc72be	1221.24 ms	1249.66 ms	28.42 ms
fc0757d	1231.83 ms	1248.98 ms	17.15 ms
f97a070	1218.88 ms	1253.12 ms	34.24 ms
f5d202b	1237.90 ms	1259.49 ms	21.59 ms
1a34ddc	1218.94 ms	1251.86 ms	32.92 ms
ea5a59b	1222.87 ms	1253.47 ms	30.60 ms
83bb978	1238.33 ms	1260.04 ms	21.71 ms
fdea6f5	1216.08 ms	1241.82 ms	25.73 ms
ccf1278	1226.84 ms	1248.51 ms	21.67 ms
9e0030e	1222.78 ms	1242.23 ms	19.45 ms

App size

Revision	Plain	With Sentry	Diff
ebc72be	23.75 KiB	908.22 KiB	884.47 KiB
fc0757d	23.75 KiB	850.73 KiB	826.98 KiB
f97a070	23.75 KiB	858.68 KiB	834.93 KiB
f5d202b	23.75 KiB	904.53 KiB	880.78 KiB
1a34ddc	23.75 KiB	919.88 KiB	896.13 KiB
ea5a59b	23.75 KiB	874.46 KiB	850.71 KiB
83bb978	23.75 KiB	920.64 KiB	896.89 KiB
fdea6f5	23.75 KiB	867.15 KiB	843.40 KiB
ccf1278	23.75 KiB	877.15 KiB	853.40 KiB
9e0030e	23.75 KiB	893.72 KiB	869.97 KiB

Previous results on branch: characterSetStatic

Startup times

Revision	Plain	With Sentry	Diff
0285b47	1227.90 ms	1258.74 ms	30.84 ms

App size

Revision	Plain	With Sentry	Diff
0285b47	23.75 KiB	920.57 KiB	896.82 KiB