use async mutex instead of std mutex

Author: lamafab

Cargo.lock

@@ -31,3 +31,4 @@ structopt = "0.3.23"
 md5 = "0.7.0"
 mongodb = { version = "2.0.0-beta", features = ["bson-u2i"] }
 bson = "2.0.0-beta"
+tokio = "1.14.0"

Cargo.toml

@@ -1,4 +1,4 @@
 description: Matrixbot Ack
 name: matrixbot-ack
-version: v0.2.5
+version: v0.2.6
 apiVersion: v2

charts/matrixbot-ack/Chart.yaml

@@ -2,7 +2,7 @@ environment: production
 
 image:
   repository: web3f/matrixbot-ack
-  tag: v0.2.5
+  tag: v0.2.6
   pullPolicy: IfNotPresent
 
 config:

charts/matrixbot-ack/values.yaml

@@ -3,7 +3,8 @@ use crate::matrix::MatrixClient;
 use crate::webhook::Alert;
 use crate::{unix_time, AlertId, Result};
 use actix::prelude::*;
-use std::sync::{Arc, Mutex};
+use tokio::sync::Mutex;
+use std::sync::Arc;
 use std::time::Duration;
 
 const CRON_JOB_INTERVAL: u64 = 5;