hw04 release

Author: richardvillagomez

_config.yml

@@ -201,7 +201,7 @@ links:
     hw01: "[Homework 01](https://data8.datahub.berkeley.edu/hub/user-redirect/git-pull?repo=https%3A%2F%2Fgithub.com%2Fdata-8%2Fmaterials-su25&urlpath=tree%2Fmaterials-su25%2Fhw%2Fhw01%2Fhw01.ipynb)"
     hw02: "[Homework 02](https://data8.datahub.berkeley.edu/hub/user-redirect/git-pull?repo=https%3A%2F%2Fgithub.com%2Fdata-8%2Fmaterials-su25&urlpath=tree%2Fmaterials-su25%2Fhw%2Fhw02%2Fhw02.ipynb)"
     hw03: "[Homework 03](https://data8.datahub.berkeley.edu/hub/user-redirect/git-pull?repo=https%3A%2F%2Fgithub.com%2Fdata-8%2Fmaterials-su25&urlpath=tree%2Fmaterials-su25%2Fhw%2Fhw03%2Fhw03.ipynb)"
-    hw04: "Homework 04"
+    hw04: "[Homework 03](https://data8.datahub.berkeley.edu/hub/user-redirect/git-pull?repo=https%3A%2F%2Fgithub.com%2Fdata-8%2Fmaterials-su25&urlpath=tree%2Fmaterials-su25%2Fhw%2Fhw04%2Fhw04.ipynb)"
     hw05: "Homework 05"
     hw06: "Homework 06"
     hw07: "Homework 07"