fix: Crash in SentryTracer when cancelling timer #6558

Job	Run time
Build test server	56s
Build test server	56s
UI Tests for ios_swift on Simulators	10m 20s
UI Tests for ios_swift on Simulators	10m 20s
UI Tests with Address Sanitizer	13m 42s
UI Tests with Address Sanitizer	13m 42s
UI Tests for ios_objc on Simulators	7m 8s
UI Tests for ios_objc on Simulators	7m 8s
UI Tests for tvos_swift on Simulators	6m 6s
UI Tests for tvos_swift on Simulators	6m 6s
UI Tests for SwiftUI on iPhone 8 (15.2) Simulator	4m 43s
UI Tests for SwiftUI on iPhone 8 (15.2) Simulator	4m 43s
UI Tests for SwiftUI on iPhone 8 (16.1) Simulator	14m 16s
UI Tests for SwiftUI on iPhone 8 (16.1) Simulator	14m 16s
Unit iOS - Xcode 13.2.1 - OS 13.7	6m 52s
Unit iOS - Xcode 13.2.1 - OS 13.7	6m 52s
Unit iOS - Thread Sanitizer	0s
Unit iOS - Thread Sanitizer	0s
Unit iOS - Xcode 13.2.1 - OS 14.5	24m 53s
Unit iOS - Xcode 13.2.1 - OS 14.5	7m 16s
Unit iOS - Xcode 13.4.1 - OS latest	5m 25s
Unit iOS - Xcode 13.4.1 - OS latest	5m 25s
Unit iOS - Xcode 14.3 - OS 16.4	7m 23s
Unit iOS - Xcode 14.3 - OS 16.4	7m 23s
Unit macOS - Xcode 13.2.1 - OS latest	3m 35s
Unit macOS - Xcode 13.2.1 - OS latest	3m 35s
Unit macOS - Xcode 13.4.1 - OS latest	4m 6s
Unit macOS - Xcode 13.4.1 - OS latest	4m 6s
Unit macOS - Xcode 14.3 - OS latest	5m 1s
Unit macOS - Xcode 14.3 - OS latest	5m 1s
Unit Catalyst - Xcode 14.3 - OS latest	4m 23s
Unit Catalyst - Xcode 14.3 - OS latest	4m 23s
Unit tvOS - Xcode 13.4.1 - OS latest	4m 11s
Unit tvOS - Xcode 13.4.1 - OS latest	4m 11s
Unit tvOS - Xcode 14.3 - OS latest	3m 59s
Unit tvOS - Xcode 14.3 - OS latest	3m 59s
	3h 56m 21s

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