l10n: Spelling unification

Signed-off-by: Valdnet <47037905+Valdnet@users.noreply.github.com>
Signed-off-by: nextcloud-command <nextcloud-command@users.noreply.github.com>

core/js/setupchecks.js

@@ -655,7 +655,7 @@
 				var xssfields = xhr.getResponseHeader('X-XSS-Protection') ? xhr.getResponseHeader('X-XSS-Protection').split(';').map(function(item) { return item.trim(); }) : [];
 				if (xssfields.length === 0 || xssfields.indexOf('1') === -1 || xssfields.indexOf('mode=block') === -1) {
 					messages.push({
-						msg: t('core', 'The "{header}" HTTP header doesn\'t contain "{expected}". This is a potential security or privacy risk, as it is recommended to adjust this setting accordingly.',
+						msg: t('core', 'The "{header}" HTTP header does not contain "{expected}". This is a potential security or privacy risk, as it is recommended to adjust this setting accordingly.',
 							{
 								header: 'X-XSS-Protection',
 								expected: '1; mode=block'