[FEATURE] Display loading mask in Extension Manager

Add a loading mask effect, whenever the User has clicked
on one of the two buttons of the compatibility check message
in the Extension Manager.

Resolves: #59498
Releases: 6.2
Change-Id: I5aed3bb5ffc4b2f0b490ec3da608b9cf33d22d06
Reviewed-on: https://review.typo3.org/30664
Reviewed-by: Fabien Udriot
Reviewed-by: Marcin Sągol
Reviewed-by: Nicole Cordes
Tested-by: Nicole Cordes
Reviewed-by: Xavier Perseguers
Tested-by: Xavier Perseguers

typo3/sysext/extensionmanager/Resources/Private/Templates/List/UnresolvedDependencies.html

@@ -20,10 +20,10 @@
 		<div class="message-body"><f:render partial="List/UnresolvedDependenciesMessage" /></div>
 	</div>
 	<br />
-	<f:link.action action="index" class="t3-button">
+	<f:link.action action="index" class="t3-button onClickMaskExtensionManager">
 		Go back
 	</f:link.action>
-	<f:link.action action="installExtensionWithoutSystemDependencyCheck" controller="Action" arguments="{extensionKey: extension.extensionKey}" class="t3-button">
+	<f:link.action action="installExtensionWithoutSystemDependencyCheck" controller="Action" arguments="{extensionKey: extension.extensionKey}" class="t3-button onClickMaskExtensionManager">
 		<span class="t3-icon t3-icon-actions t3-icon-dialog-error">&nbsp;</span> <f:translate key="dependencyCheck.unresolvedDependencies.proceed" />
 	</f:link.action>
 </f:section>
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