Bump device-mgt core,plugins snapshot version

pom.xml

@@ -322,14 +322,14 @@
         <entgra-uem-community>entgra-uem-community-${project.version}</entgra-uem-community>
 
         <!-- Carbon Device Management-->
-        <io.entgra.device.mgt.core.version>5.0.27</io.entgra.device.mgt.core.version>
+        <io.entgra.device.mgt.core.version>5.0.28-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>6.0.18</io.entgra.device.mgt.plugins.version>
+        <io.entgra.device.mgt.plugins.version>6.0.19-SNAPSHOT</io.entgra.device.mgt.plugins.version>
 
         <!--Testing-->
         <google.gson.version>2.8.5</google.gson.version>