[STATS] get app name from app.name rather than restx.appName

app.name is what is set in generated settings when using app new.

restx.appName seems to be used very infrequently, currently we only have 4 different appNameHash
collected on 1000+ hosts.

Author: xhanin

restx-stats-admin/src/main/java/restx/stats/RestxStatsCollector.java

@@ -79,7 +79,7 @@ public class RestxStatsCollector implements AutoStartable, AutoCloseable {
     private volatile long lastShareTime;
 
     public RestxStatsCollector(
-            @Named("restx.appName") Optional<String> appName,
+            @Named("app.name") Optional<String> appName,
             @Named("restx.server.type") Optional<String> serverType,
             @Named("restx.server.port") Optional<String> serverPort,
             AppSettings appSettings, RestxStatsSettings statsSettings,