[BUGFIX] Do not allow dots in ratio IDs

Due to usage of Fluid dynamic variable parts in the template,
ratio IDs must not contain a "."

Resolves: #80214
Releases: master
Change-Id: I12dac926169c827c9e3022320dd90a058f72913b
Reviewed-on: https://review.typo3.org/52194


Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Tested-by: Jigal van Hemert <jigal.van.hemert@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>