chore: Cleanup some unreachable code after v9

[noahsmartin]

The kSentryLaunchProfileConfigKeyContinuousProfilingV2 key isn't needed anymore because continuousV2 is now the only profiling mode in V9

#skip-changelog

Closes #6600

[codecov]

❌ 1 Tests Failed:

Tests completed	Failed	Passed	Skipped
3883	1	3882	52

View the top 1 failed test(s) by shortest run time

iOS_SwiftUI_UITests.LaunchUITests::testNoNewTransactionForSecondCallToBody

Stack Traces | 0s run time

.../iOS-SwiftUI/iOS-SwiftUI-UITests/LaunchUITests.swift:37 - Failed to tap "Form Screen" Button: Timed out while evaluating UI query.

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[itaybre]

LGTM, I wonder if we could remove the V2 since that's all what we will have after v9

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1224.35 ms	1259.36 ms	35.01 ms
Size	23.75 KiB	1.02 MiB	1016.33 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
7c7ac56	1225.90 ms	1250.22 ms	24.33 ms
134fbdf	1219.71 ms	1240.35 ms	20.64 ms
f92cfa9	1228.45 ms	1251.33 ms	22.88 ms
2ca8f2e	1207.08 ms	1235.58 ms	28.49 ms
75b23cd	1227.10 ms	1253.61 ms	26.51 ms
6ee4973	1228.42 ms	1252.26 ms	23.84 ms
25f4532	1203.28 ms	1240.71 ms	37.44 ms
d8ceea3	1234.15 ms	1263.92 ms	29.77 ms
be8375a	1212.65 ms	1239.72 ms	27.08 ms
b9c733a	1195.49 ms	1220.23 ms	24.74 ms

App size

Revision	Plain	With Sentry	Diff
7c7ac56	23.75 KiB	902.49 KiB	878.74 KiB
134fbdf	23.75 KiB	875.25 KiB	851.50 KiB
f92cfa9	23.75 KiB	855.38 KiB	831.62 KiB
2ca8f2e	23.74 KiB	996.96 KiB	973.21 KiB
75b23cd	23.75 KiB	933.66 KiB	909.92 KiB
6ee4973	23.75 KiB	896.53 KiB	872.79 KiB
25f4532	23.75 KiB	969.27 KiB	945.52 KiB
d8ceea3	23.75 KiB	980.81 KiB	957.07 KiB
be8375a	23.75 KiB	933.03 KiB	909.28 KiB
b9c733a	23.74 KiB	1021.49 KiB	997.74 KiB