feat: add type definition

[dojineko]

Added TypeScript type definitions for redis-lock 1.0.0

fix: #36
ref: misskey-dev/misskey#9971

The following is a record of how JSDoc handles this issue. If it is necessary, I would like to change the means of implementation.

+ /**
+  * @param {import('redis').RedisClientType} client
+  * @param {string} lockName
+  * @param {number} timeout
+  * @param {number} retryDelay
+  * @param {(timeout: number) => void} onLockAcquired
+  */
  async function acquireLock (client, lockName, timeout, retryDelay, onLockAcquired) {

+ /**
+  * @param {import('redis').RedisClientType} client
+  * @param {number} retryDelay
+  */
  function redisLock (client, retryDelay = DEFAULT_RETRY_DELAY) {

+     /**
+      * @param {string} lockName 
+      * @param {number} timeout
+      * @returns {Promise<string | undefined>}
+      */
      async function lock (lockName, timeout = DEFAULT_TIMEOUT) {

[rostamiani]

The function output is not a Promise<string | undefined>, It's a function and should be Promise<() => Promise<void>>