[BUGFIX] Properly set format of StandaloneView

The internal TemplatePaths object of the BaseRenderingContext
needs to updated as well, when the format of a view is changed.

Resolves: #81003
Releases: master, 8.7
Change-Id: Ibb157f6f042b387ba008d1c9cebfcf3a3681141b
Reviewed-on: https://review.typo3.org/52594


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Johannes Kasberger <johannes.kasberger@reelworx.at>
Tested-by: Johannes Kasberger <johannes.kasberger@reelworx.at>
Reviewed-by: Claus Due <claus@phpmind.net>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Thomas Hohn <thomas@hohn.dk>
Reviewed-by: Tymoteusz Motylewski <t.motylewski@gmail.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>