* Adding host:port validation checks to ES plugin & Redis plugin
Also correcting the assertions in the RedisPluginTest so that the error message on test failure is accurate.
* Removing the endpoint validation from datasourceServiceImpl
Moving the endpoint validation to the plugin implementation classes because there are databases that require complete HTTP URL in their configuration. Checking for http/https at the platform level affects the UX for the user & plugin developer when using a new integration. Hence, all plugins must implement their own client/server validations in their own implementations
* Adding tests to assert hostname validation in mysql & postgres plugins
1. Fixing the build by excluding the slf4j-api from redis-plugin pom.xml
2. Adding the editor.json and form.json for the query pane & datasource pane.
3. Adding array handling in the Redis response by feeding all the output into a "result" key
