chore: Remove swift5.9 checks

[itaybre]

📜 Description

Remove Swift 5.9 checks since we are building with Xcode 16 now.

💡 Motivation and Context

The motivation is removing unnecessary code in our codebase.

💚 How did you test it?

Make sure the library builds on Xcode locally

📝 Checklist

You have to check all boxes before merging:

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

Closes #7099

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.773%. Comparing base (f3bb63c) to head (0273d55).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@              Coverage Diff              @@
##              main     #7098       +/-   ##
=============================================
+ Coverage   84.769%   84.773%   +0.003%     
=============================================
  Files          459       459               
  Lines        27517     27517               
  Branches     12132     12136        +4     
=============================================
+ Hits         23326     23327        +1     
  Misses        4149      4149               
+ Partials        42        41        -1     

Files with missing lines	Coverage Δ
SentryTestUtils/Sources/TestOptions.swift	100.000% <ø> (ø)
Sources/Swift/AppState/SentryAppStateManager.swift	100.000% <ø> (ø)
...egrations/FramesTracking/SentryFramesTracker.swift	100.000% <ø> (ø)
...tegrations/FramesTracking/SentryScreenFrames.swift	100.000% <ø> (ø)
Sources/Swift/Core/Integrations/Integrations.swift	100.000% <ø> (ø)
Sources/Swift/Helper/SentrySDK.swift	84.259% <ø> (ø)
Sources/Swift/Helper/SentrySwizzleWrapper.swift	93.750% <ø> (ø)
.../Swift/Integrations/Log/FlushLogsIntegration.swift	90.476% <ø> (ø)
...rations/Performance/SentryDisplayLinkWrapper.swift	100.000% <ø> (ø)
...nce/SentryUIViewControllerPerformanceTracker.swift	100.000% <ø> (ø)
... and 4 more

... and 2 files with indirect coverage changes

---

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[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1215.00 ms	1238.35 ms	23.35 ms
Size	24.14 KiB	1.03 MiB	1.00 MiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
9ec4c56	1222.69 ms	1248.77 ms	26.08 ms
2699f74	1229.90 ms	1264.60 ms	34.71 ms
130c6ba	1237.02 ms	1259.67 ms	22.65 ms
856fffe	1232.69 ms	1245.80 ms	13.10 ms
f4f94f5	1216.24 ms	1247.94 ms	31.70 ms
aa643c5	1228.25 ms	1261.08 ms	32.83 ms
82f60cf	1218.65 ms	1238.52 ms	19.87 ms
a2a3bfb	1227.94 ms	1261.26 ms	33.32 ms
d3b0d62	1234.78 ms	1262.69 ms	27.91 ms
6502818	1229.08 ms	1245.46 ms	16.37 ms

App size

Revision	Plain	With Sentry	Diff
9ec4c56	23.75 KiB	921.20 KiB	897.45 KiB
2699f74	24.14 KiB	1023.19 KiB	999.04 KiB
130c6ba	23.75 KiB	926.65 KiB	902.89 KiB
856fffe	23.75 KiB	975.18 KiB	951.44 KiB
f4f94f5	23.75 KiB	988.02 KiB	964.27 KiB
aa643c5	23.75 KiB	1015.07 KiB	991.32 KiB
82f60cf	23.75 KiB	913.63 KiB	889.88 KiB
a2a3bfb	23.75 KiB	872.67 KiB	848.92 KiB
d3b0d62	23.75 KiB	913.42 KiB	889.67 KiB
6502818	23.75 KiB	959.45 KiB	935.70 KiB