[mattermostGH-902]:Added check to uninstall server if not found in KV…

… store (mattermost#914)

* [MI-2738]:Added check to uninstall server if not found in KV store (#34)

* [MI-2738]:Added check to uninstall server if not found in KV store

* [MI-2738]:Fixed lint errors

* [MM-902]:Fixed review comment

* [MI-2781]:Fixed review comments for issue mattermost#902 and PR mattermost#914 on jira plugin (#36)

* [MM-902]:Reverted the changes

* [MM-902]:Reverted the disconnect users function

server/instances.go

@@ -5,6 +5,7 @@ package main
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/pkg/errors"
@@ -187,6 +188,15 @@ func (p *Plugin) UninstallInstance(instanceID types.ID, instanceType InstanceTyp
 			var err error
 			instance, err = p.instanceStore.LoadInstance(instanceID)
 			if err != nil {
+				if strings.Contains(err.Error(), "not found") {
+					instances.Delete(instanceID)
+					if err = p.instanceStore.StoreInstances(instances); err != nil {
+						return err
+					} else {
+						return nil
+					}
+				}
+
 				return err
 			}
 			if instanceType != instance.Common().Type {