Liang Zhang

[Bug][framework] status code 500 returned from the server

1

### Search before asking - [X] I had searched in the [issues](https://github.com/apache/incubator-devlake/issues?q=is%3Aissue) and found no similar issues. ### What happened status code 500 returned from the endpoint `/pipelines` ``` $...

fix a typo in algebraic_topology_iii.tex