[BUGFIX] HTML contained in variables must be unescaped in ButtonBar partial

As the topic says: `f:format.raw` must be implemented here.

Change-Id: I94ad04711e77c1e050ee3c3f1086ec5d3f7f1a35
Resolves: #71693
Releases: master
Reviewed-on: https://review.typo3.org/44801


Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>

typo3/sysext/backend/Resources/Private/Partials/ButtonBar.html

@@ -4,13 +4,13 @@
 			<f:then>
 				<div class="btn-group" role="group" aria-label="">
 					<f:for each="{buttonGroup}" as="button">
-						{button}
+						{button -> f:format.raw()}
 					</f:for>
 				</div>
 			</f:then>
 			<f:else>
-				{buttonGroup.0}
+				{buttonGroup.0 -> f:format.raw()}
 			</f:else>
 		</f:if>
 	</f:for>
-</div>
\ No newline at end of file
+</div>