Bump device-mgt-core and device-mgt-plugins snapshot versions

pom.xml

@@ -323,14 +323,14 @@
         <entgra-iot-community>entgra-iots-community-${project.version}</entgra-iot-community>
 
         <!-- Carbon Device Management-->
-        <io.entgra.device.mgt.core.version>5.1.0</io.entgra.device.mgt.core.version>
+        <io.entgra.device.mgt.core.version>5.1.1-SNAPSHOT</io.entgra.device.mgt.core.version>
 
         <carbon.p2.plugin.version>5.1.2</carbon.p2.plugin.version>
 
         <!--Orbit versions-->
         <orbit.h2.engine.version>1.4.199.wso2v1</orbit.h2.engine.version>
 
-        <io.entgra.device.mgt.plugins.version>6.1.0</io.entgra.device.mgt.plugins.version>
+        <io.entgra.device.mgt.plugins.version>6.1.1-SNAPSHOT</io.entgra.device.mgt.plugins.version>
 
         <!--Testing-->
         <google.gson.version>2.8.5</google.gson.version>