avoid KeyError when track is already unpublished #1620

Job	Run time
Make RTC sdist	17s
Build RTC wheels (x86_64 arm64)	52s
Build RTC wheels (AMD64)	1m 6s
Generating protobuf	15s
Build RTC wheels (x86_64)	1m 4s
Build RTC wheels (aarch64)	1m 18s
Test (ubuntu-latest, Python 3.12) / Test (ubuntu-latest, Python 3.12)	1m 32s
Test (ubuntu-latest, Python 3.9) / Test (ubuntu-latest, Python 3.9)	1m 33s
Test (windows-latest, Python 3.9) / Test (windows-latest, Python 3.9)	2m 26s
Test (windows-latest, Python 3.12) / Test (windows-latest, Python 3.12)	1m 51s
Test (macos-latest, Python 3.12) / Test (macos-latest, Python 3.12)	2m 4s
Test (windows-latest, Python 3.14) / Test (windows-latest, Python 3.14)	1m 55s
Test (ubuntu-latest, Python 3.10) / Test (ubuntu-latest, Python 3.10)	1m 36s
Test (ubuntu-latest, Python 3.11) / Test (ubuntu-latest, Python 3.11)	1m 26s
Test (macos-latest, Python 3.14) / Test (macos-latest, Python 3.14)	1m 48s
Test (ubuntu-latest, Python 3.14) / Test (ubuntu-latest, Python 3.14)	1m 25s
Test (macos-latest, Python 3.9) / Test (macos-latest, Python 3.9)	2m 1s
Test (ubuntu-latest, Python 3.13) / Test (ubuntu-latest, Python 3.13)	1m 28s
Publish RTC release	0s
docs	0s
	25m 57s

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