fix: image location for location input with two parts

[timwangmusic]

Description

When users use locations with only city followed by country (e.g. Paris, France), the image is stored under / with the current implementation. In this fix, the images will be stored in country/cities/city_name directory in the S3 bucket.

Solution

• Add a simple validation in the image fetcher.
• Add a fixed filler for location inputs without admin area one.

Testing

• Integration testing on Heroku staging
• Added new unit tests

Checks

• Have you removed commented code?
• Have you used gofmt to format your code?

[sananand007]

lg