Switch to native browser tooltips

[juliusknorr]

As an accessibility requirement we should drop any usage of the custom v-tooltip directive / Tooltip from @nextcloud/vue and use native browser tooltips (with the title attribute instead). Usages should be easy to find:

components/Menu/EmojiPickerAction.vue
27:		<NcButton v-tooltip="actionEntry.label"

components/Editor/GuestNameDialog.vue
24:	<form v-tooltip="t('text', 'Enter your name so other people can see who is editing')" class="guest-name-dialog" @submit.prevent="setGuestName()">
49:		tooltip: Tooltip,

components/Editor/AvatarWrapper.vue
8:			:disable-tooltip="true"

components/Editor/SessionList.vue
26:			v-tooltip.bottom="label"
80:		tooltip: Tooltip,

components/Menu/ActionSingle.vue
101:			tooltip,
107:		// do not use tooltip if is a item of action list
111:				name: 'tooltip',
112:				value: tooltip,

components/Menu/ActionList.vue
24:	<NcActions v-tooltip="tooltip"

components/Editor/Status.vue
25:		<div v-tooltip="lastSavedStatusTooltip" class="save-status" :class="saveStatusClass">

components/Menu/BaseActionEntry.js
68:		tooltip() {

Also fixes #4234