Fix prerelease and release-channel vars #761

Job	Run time
build-frontend	20s
getvars / get-vars	9s
build-firmware (Wemos-D1-Mini-ESP32)	1m 11s
build-firmware (Wemos-Lolin-S2-Mini)	1m 27s
build-firmware (Wemos-Lolin-S3)	1m 32s
build-firmware (Pishock-2023)	1m 6s
build-firmware (Pishock-Lite-2021)	1m 8s
build-firmware (Seeed-Xiao-ESP32S3)	1m 30s
build-firmware (OpenShock-Core-V1)	1m 25s
build-staticfs	42s
merge-partitions (Wemos-D1-Mini-ESP32)	12s
merge-partitions (Wemos-Lolin-S2-Mini)	16s
merge-partitions (Wemos-Lolin-S3)	19s
merge-partitions (Pishock-2023)	11s
merge-partitions (Pishock-Lite-2021)	22s
merge-partitions (Seeed-Xiao-ESP32S3)	22s
merge-partitions (OpenShock-Core-V1)	12s
checkpoint-build	1s
cdn-upload-version-info	7s
cdn-upload-firmware (Wemos-D1-Mini-ESP32)	18s
cdn-upload-firmware (Wemos-Lolin-S2-Mini)	18s
cdn-upload-firmware (Wemos-Lolin-S3)	17s
cdn-upload-firmware (Pishock-2023)	13s
cdn-upload-firmware (Pishock-Lite-2021)	24s
cdn-upload-firmware (Seeed-Xiao-ESP32S3)	18s
cdn-upload-firmware (OpenShock-Core-V1)	11s
cdn-bump-version	8s
checkpoint-cdn	1s
release	0s
	14m 40s

Provide feedback