Implement plugin KV store in memory (#26244)

server/public/pluginapi/experimental/common/kvstore.go

@@ -2,7 +2,6 @@ package common
 
 import (
 	"errors"
-	"time"
 
 	"github.com/mattermost/mattermost/server/public/pluginapi"
 )
@@ -11,9 +10,6 @@ var ErrNotFound = errors.New("not found")
 
 type KVStore interface {
 	Set(key string, value interface{}, options ...pluginapi.KVSetOption) (bool, error)
-	SetWithExpiry(key string, value interface{}, ttl time.Duration) error
-	CompareAndSet(key string, oldValue, value interface{}) (bool, error)
-	CompareAndDelete(key string, oldValue interface{}) (bool, error)
 	Get(key string, o interface{}) error
 	Delete(key string) error
 	DeleteAll() error