Install maxminddb package in CI again

We no longer need to install from Git.

Author: oschwald

.travis.yml

@@ -22,7 +22,6 @@ before_install:
   - sudo make install
   - sudo ldconfig
   - cd ..
-  - pip install -e git+https://github.com/maxmind/MaxMind-DB-Reader-python#egg=maxminddb
   - "if [[ $RUN_SNYK && $SNYK_TOKEN ]]; then sudo apt-get install -y nodejs; npm install -g snyk; fi"
 install:
   - pip install -r requirements.txt