message: types: add type for this on event listeners callbacks
diff: @@ -541,18 +541,27 @@ class Curl extends EventEmitter {
  * Overloaded methods for the Curl class.
  */
  interface Curl {
  - on(event: 'data', listener: (chunk: Buffer, curlInstance: Curl) => void): this
  + on(
  + event: 'data',
  + listener: (this: Curl, chunk: Buffer, curlInstance: Curl) => void,
  + ): this
  on(
  event: 'header',
  - listener: (chunk: Buffer, curlInstance: Curl) => void,
  + listener: (this: Curl, chunk: Buffer, curlInstance: Curl) => void,
  ): this
  on(
  event: 'error',
  - listener: (error: Error, errorCode: CurlCode, curlInstance: Curl) => void,
  + listener: (
  + this: Curl,
  + error: Error,
  + errorCode: CurlCode,
  + curlInstance: Curl,
  + ) => void,
  ): this
  on(
  event: 'end',
  listener: (
  + this: Curl,
  status: number,
  data: string | Buffer,
  headers: Buffer | HeaderInfo[],
  