[BUGFIX] Allow setting "ready to publish" workspace state again

[BUGFIX] Allow setting "ready to publish" workspace state again

The "ready to publish" workspace state has the internal negative
identifier -10 which is not supported anymore since system fields
are auto-generated and t3ver_stage defined to be of type unsigned
(positive) integer.

Resolves: #85345
Releases: master
Change-Id: I2cb1f3f5bc65ec30fb510c5f2d2f9fbb9e0d55e9
Reviewed-on: https://review.typo3.org/57301
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Reviewed-by: Aljoscha Weber <aweber@w-commerce.de>
Tested-by: Aljoscha Weber <aweber@w-commerce.de>
Reviewed-by: Jonas Götze <jonnsn@gmail.com>
Tested-by: Jonas Götze <jonnsn@gmail.com>
Reviewed-by: Susanne Moog <susanne.moog@typo3.org>
Tested-by: Susanne Moog <susanne.moog@typo3.org>