MM-21626, MM-21627 - Plugin API/Hooks Prometheus instrumentati… (#13825)

* MM-21626,MM-21627 - Plugin API/Hooks Prometheus instrumentation

* Updated einterface mocks

* Fixed supervisor tests

* ignoring golint errors for plugin metrics wrappers

* Making golangci happy

* Using variadic form when generating wrapper code

* Removed artificial delay

* Removed comments from tests

* Renaming plugin wrappers to api/hooks_timer_layer

* updating vendor dir and mod files

* Recording plugin api/hook responses in prometheus

* Updated einterfaces-mocks

* Updating go sum

* Updating go sum

* Fixing conflicts

* More conflicts fixing

Co-authored-by: mattermod <mattermod@users.noreply.github.com>

einterfaces/mocks/MessageExportJobInterface.go

@@ -4,8 +4,10 @@
 
 package mocks
 
-import mock "github.com/stretchr/testify/mock"
-import model "github.com/mattermost/mattermost-server/v5/model"
+import (
+	model "github.com/mattermost/mattermost-server/v5/model"
+	mock "github.com/stretchr/testify/mock"
+)
 
 // MessageExportJobInterface is an autogenerated mock type for the MessageExportJobInterface type
 type MessageExportJobInterface struct {