fix test file name

[4geru]

Background

test target file name and test file name is different. class name is GeoLoc so fixed geo_loc file.

• target file: geo_loc.rb
• test file : test_geoloc.rb

[coveralls]

Coverage remained the same at 96.296% when pulling e473c7d on 4geru:rename_from_test_geoloc_to_test_geo_loc_for_GeoLoc_class_test into b7c1337 on geokit:master.

[dsantosmerino]

Thanks for your first contribution, @4geru!