test: Add SentryFileManagerTest to flaky plans

[philipphofmann]

Add testCreateDirectoryIfNotExists_successful_shouldNotLogError to the flaky plan.

Failed here: https://github.com/getsentry/sentry-cocoa/actions/runs/19233074305/job/54976002030

#skip-changelog

Closes #6736

[codecov]

❌ 1 Tests Failed:

Tests completed	Failed	Passed	Skipped
3952	1	3951	55

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

iOS_Swift6_UITests.UITests::testLaunchAndCaptureError

Stack Traces | 0s run time

.../iOS-Swift6/iOS-Swift6-UITests/UITests.swift:11 - Failed to get background assertion for target app with pid 11272: Timed out while acquiring background assertion.

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[itaybre]

No need to remove them from the other plan?

[philipphofmann]

No need to remove them from the other plan?

@itaybre, Sentry_Base has a skipped list.

sentry-cocoa/Plans/Sentry_Base.xctestplan

Lines 29 to 59 in ee1f2ca

	"skippedTests" : [
	"PrivateSentrySDKOnlyTests\/testProfilingStartAndCollect()",
	"SentryANRTrackerTests\/testANRButAppInBackground_NoANR()",
	"SentryANRTrackerTests\/testMultipleListeners()",
	"SentryCoreDataTrackerTests\/testFetchRequestBackgroundThread()",
	"SentryCoreDataTrackerTests\/testSaveBackgroundThread()",
	"SentryCrashBinaryImageCacheTests\/testRemoveImageFromBeginning",
	"SentryCrashIntegrationTests\/testStartUpCrash_CallsFlush()",
	"SentryCrashReportStore_Tests\/testCrashReportCount1",
	"SentryCrashReportStore_Tests\/testDeleteAllReports",
	"SentryCrashReportStore_Tests\/testPruneReports",
	"SentryCrashReportStore_Tests\/testStoresLoadsMultipleReports",
	"SentryFileManagerTests\/testCreateDirectoryIfNotExists_successful_shouldNotLogError()",
	"SentryHttpTransportFlushIntegrationTests",
	"SentryHttpTransportTests\/testFlush_WhenNoInternet_BlocksAndFinishes()",
	"SentryNetworkTrackerIntegrationTestServerTests",
	"SentryNetworkTrackerIntegrationTestServerTests\/testGetRequest_SpanCreatedAndBaggageHeaderAdded()",
	"SentryOnDemandReplayTests\/testAddFrameIsThreadSafe()",
	"SentryProfilerSwiftTests\/testConcurrentSpansWithTimeout()",
	"SentryReachabilityTest\/testMultipleReachabilityObservers",
	"SentrySDKIntegrationTestsBase",
	"SentrySDKInternalTests\/testResumeAndPauseAppHangTracking()",
	"SentrySDKTests\/testStartOnTheMainThread()",
	"SentrySessionGeneratorTests\/testSendSessions()",
	"SentrySubClassFinderTests\/testActOnSubclassesOfViewController()",
	"SentryThreadInspectorTests\/testGetCurrentThreadsWithStacktrace_WithSymbolication()",
	"SentryThreadInspectorTests\/testStacktraceHasFrames_forEveryThread()",
	"SentryThreadWrapperTests\/testOnMainThreadFromNonMainContext()",
	"SentryTracerTests\/testDeadlineTimer_StartedAndCancelledOnMainThread()",
	"SentryWatchdogTerminationTrackerTests\/testTerminateApp_RunsOnMainThread()"
	],