refactor: pattern ban-types between Connection and Pool

Author: wellwelwel

index.d.ts

@@ -160,6 +160,7 @@ export interface Pool extends mysql.Connection {
     callback: (err: NodeJS.ErrnoException, connection: PoolConnection) => any
   ): void;
   releaseConnection(connection: PoolConnection | PromisePoolConnection): void;
+  on(event: string, listener: (args: any[]) => void): this;
   on(event: 'connection', listener: (connection: PoolConnection) => any): this;
   on(event: 'acquire', listener: (connection: PoolConnection) => any): this;
   on(event: 'release', listener: (connection: PoolConnection) => any): this;

typings/mysql/lib/Connection.d.ts

@@ -375,7 +375,7 @@ declare class Connection extends EventEmitter {
 
   format(sql: string, values?: any | any[] | { [param: string]: any }): string;
 
-  on(event: string, listener: Function): this;
+  on(event: string, listener: (args: any[]) => void): this;
 
   rollback(callback: (err: Query.QueryError | null) => void): void;
 

typings/mysql/lib/Pool.d.ts

@@ -200,7 +200,7 @@ declare class Pool extends EventEmitter {
     callback?: (err: NodeJS.ErrnoException | null, ...args: any[]) => any
   ): void;
 
-  on(event: string, listener: Function): this;
+  on(event: string, listener: (args: any[]) => void): this;
   on(event: 'connection', listener: (connection: PoolConnection) => any): this;
 
   promise(promiseImpl?: PromiseConstructor): PromisePool;