Update auth-client to 2.5.0 to pick up CSRF optimization (#407)

Author: Blackbaud-PaulCrowder

package.json

@@ -42,7 +42,7 @@
     "@angular/platform-browser": "4.3.6",
     "@angular/platform-browser-dynamic": "4.3.6",
     "@angular/router": "4.3.6",
-    "@blackbaud/auth-client": "2.4.0",
+    "@blackbaud/auth-client": "2.5.0",
     "@blackbaud/skyux-lib-help": "1.3.0",
     "@blackbaud/skyux-logger": "1.0.2",
     "@ngtools/webpack": "1.3.1",