Whitelist /plugins/ endpoint

GerritTriggerPlugin from Jenkins was incompatibile with this plugin
since GerritMissedEventsPlaybackEnabledChecker component is trying to
perform "GET /plugins/events-log/ HTTP/1.1" in order to check whether
events-log plugin is installed. With previous version this will return
login page with 401 which results in assumming that plugin is not
installed.

Change-Id: Ie1fe3bcbe7c590911a3f63e3ee47ede741083081
diff --git a/src/main/java/com/googlesource/gerrit/plugins/loginredirect/LoginRedirectFilter.java b/src/main/java/com/googlesource/gerrit/plugins/loginredirect/LoginRedirectFilter.java
index 87fb6c3..3da3598 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/loginredirect/LoginRedirectFilter.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/loginredirect/LoginRedirectFilter.java
@@ -46,6 +46,7 @@
         || path.equals("/login")
         || path.startsWith("/login/")
         || path.equals("/oauth")
+        || path.startsWith("/plugins/")
         || path.equals("/ssh_info")
         || path.startsWith("/static/")
         || path.startsWith("/tools/hooks/")