Fix for 'SafeConfigParser' AttributeError in Versioneer

[ksy141]

I was trying to install the develop branch but ran into an issue related to versioneer, receiving the following error message:

AttributeError: module configparser has no attribute SafeConfigParser. Did you mean: RawConfigParser?

I was able to resolve this by following a suggestion from an unrelated GitHub discussion that addressed the same problem: pydata/pandas-datareader#969.

Specifically, I replaced SafeConfigParser with ConfigParser and readfp with read_file in versioneer.py. I'm sharing this solution in case others encounter the same issue.