fix: Remove raw loop in log serialization

[noahsmartin]

Raw loops scare me, and so does immutable state, so update this to not use a loop and to have a let constant.

#skip-changelog

Closes #6980

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.094%. Comparing base (98e0ee8) to head (950af06).
⚠️ Report is 9 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #6979       +/-   ##
=============================================
+ Coverage   85.038%   85.094%   +0.055%     
=============================================
  Files          453       453               
  Lines        27664     27674       +10     
  Branches     12154     12164       +10     
=============================================
+ Hits         23525     23549       +24     
+ Misses        4095      3868      -227     
- Partials        44       257      +213     

Files with missing lines	Coverage Δ
Sources/Swift/Tools/SentryLogBatcher.swift	98.437% <100.000%> (-0.082%)	⬇️

... and 43 files with indirect coverage changes

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[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1230.59 ms	1252.65 ms	22.06 ms
Size	24.14 KiB	1.02 MiB	1019.78 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
0ede342	1233.47 ms	1262.29 ms	28.82 ms
d05d866	1211.78 ms	1230.96 ms	19.18 ms
bbe6658	1221.00 ms	1248.51 ms	27.51 ms
bc0a04c	1226.83 ms	1255.04 ms	28.21 ms
15a6325	1209.43 ms	1233.43 ms	24.00 ms
25d9b58	1233.76 ms	1267.92 ms	34.16 ms
532bde4	1210.63 ms	1256.24 ms	45.61 ms
f83dcc4	1210.88 ms	1246.22 ms	35.35 ms
449d185	1216.31 ms	1251.94 ms	35.62 ms
dad68ad	1229.15 ms	1261.98 ms	32.83 ms

App size

Revision	Plain	With Sentry	Diff
0ede342	23.75 KiB	928.15 KiB	904.40 KiB
d05d866	23.75 KiB	878.60 KiB	854.85 KiB
bbe6658	23.75 KiB	908.02 KiB	884.27 KiB
bc0a04c	23.75 KiB	933.32 KiB	909.57 KiB
15a6325	23.75 KiB	933.33 KiB	909.58 KiB
25d9b58	24.15 KiB	1.01 MiB	1014.91 KiB
532bde4	24.15 KiB	1.01 MiB	1014.89 KiB
f83dcc4	23.75 KiB	1.02 MiB	1019.11 KiB
449d185	23.75 KiB	980.81 KiB	957.06 KiB
dad68ad	23.75 KiB	912.37 KiB	888.63 KiB