at the moment the loop that run the Jump animation is infinite because 

    if (run == true) { // this condition is always TRUE once the player press R.
      
we can avoid it by changing that into a diffrent boolean that doesnt effect the running animation itself as I can only guess that when RUN equals TRUE the player is running so the following code should solve this problem.

    public bool run = false;
    public bool jump = false;
    void Start () {
    
    
    }
    
    void Update () {
        if(Input.GetKey(KeyCode.R))
            {
            run = true;
            jump = true
            }
        if (jump == true) { 
          GetComponent<Animation>().Play("Jump");
          GetComponent<Animation>().wrapMode = WrapMode.Loop;
          jump == false; // now the player will run and jump one time after he press the key R.
        }
    
    }