fix(test): Fix flaky previous session finalization test

[adinauer]

Fix flaky test if there is work enqueued, init finalizes previous session after that work is done in SentryTest.

The test submits work to the single-threaded executor that reads the previous session file and sets a triggered flag. Sentry.init then enqueues the PreviousSessionFinalizer (which deletes the file) as a separate task after the test's task. The test was waiting for triggered to become true and then immediately asserting the file was deleted — but since the finalizer is a separate queued task, there's a race where the assertion runs before the finalizer has executed.

Replace the immediate assertFalse(previousSessionFile.exists()) with await.until { !previousSessionFile.exists() } to poll until the finalizer completes.

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[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	307.08 ms	354.66 ms	47.58 ms
Size	1.58 MiB	2.29 MiB	723.38 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
91bb874	310.68 ms	359.24 ms	48.56 ms
e59e22a	368.02 ms	432.00 ms	63.98 ms
fc5ccaf	279.11 ms	353.34 ms	74.23 ms
d15471f	315.20 ms	370.22 ms	55.02 ms
d15471f	286.65 ms	314.68 ms	28.03 ms
d15471f	342.08 ms	415.44 ms	73.35 ms
ad8da22	314.38 ms	352.29 ms	37.91 ms
cf708bd	434.73 ms	502.96 ms	68.22 ms
abfcc92	309.54 ms	380.32 ms	70.78 ms
91bb874	314.47 ms	440.00 ms	125.53 ms

App size

Revision	Plain	With Sentry	Diff
91bb874	1.58 MiB	2.13 MiB	559.07 KiB
e59e22a	1.58 MiB	2.20 MiB	635.34 KiB
fc5ccaf	1.58 MiB	2.13 MiB	557.54 KiB
d15471f	1.58 MiB	2.13 MiB	559.54 KiB
d15471f	1.58 MiB	2.13 MiB	559.54 KiB
d15471f	1.58 MiB	2.13 MiB	559.54 KiB
ad8da22	1.58 MiB	2.29 MiB	719.83 KiB
cf708bd	1.58 MiB	2.11 MiB	539.71 KiB
abfcc92	1.58 MiB	2.13 MiB	557.31 KiB
91bb874	1.58 MiB	2.13 MiB	559.07 KiB