Add icon to admin page sidebar for LDAP

* follow up to nextcloud/server#3151

Signed-off-by: Morris Jobke <hey@morrisjobke.de>

apps/user_ldap/img/app-dark.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns="http://www.w3.org/2000/svg" height="16" width="16" version="1.0" viewBox="0 0 16 16">
+	<path style="block-progression:tb;color:#000000;text-transform:none;text-indent:0" fill="#000" d="m8.4036 1c-1.7312 0-3.1998 1.2661-3.1998 2.9 0.012287 0.51643 0.058473 1.1532 0.36664 2.5v0.033333l0.033328 0.033333c0.098928 0.28338 0.24289 0.44549 0.4333 0.66666s0.41742 0.48149 0.63328 0.69999c0.025397 0.025708 0.041676 0.041633 0.066656 0.066677 0.04281 0.18631 0.094672 0.38681 0.13332 0.56666 0.10284 0.47851 0.092296 0.81737 0.066668 0.93332-0.74389 0.26121-1.6694 0.57228-2.4998 0.93332-0.46622 0.2027-0.8881 0.3837-1.2332 0.59999-0.34513 0.2163-0.68837 0.37971-0.79994 0.86666-0.16004 0.63293-0.19866 0.7539-0.39997 1.5333-0.027212 0.20914 0.083011 0.42961 0.26665 0.53333 1.5078 0.81451 3.824 1.1423 6.1329 1.1333s4.6066-0.35609 6.0662-1.1333c0.11739-0.07353 0.14304-0.10869 0.13332-0.2333-0.04365-0.68908-0.08154-1.3669-0.13332-1.7666-0.01807-0.09908-0.06492-0.19275-0.13332-0.26666-0.46366-0.5537-1.1564-0.89218-1.9665-1.2333-0.7396-0.31144-1.6067-0.63486-2.4665-0.99999-0.048123-0.10721-0.095926-0.41912 0-0.89999 0.025759-0.12912 0.066096-0.26742 0.099994-0.4 0.0808-0.090507 0.14378-0.16447 0.23332-0.26666 0.19096-0.21796 0.39614-0.44661 0.56662-0.66666s0.30996-0.40882 0.39997-0.66666l0.03333-0.033333c0.34839-1.4062 0.34857-1.9929 0.36664-2.5v-0.033333c0-1.6339-1.4686-2.9-3.1998-2.9z"/>
+</svg>

apps/user_ldap/lib/Settings/Section.php

@@ -77,6 +77,6 @@ class Section implements IIconSection {
 	 * {@inheritdoc}
 	 */
 	public function getIcon() {
-		return $this->url->imagePath('user_ldap', 'app.svg');
+		return $this->url->imagePath('user_ldap', 'app-dark.svg');
 	}
 }