Update/stub Geocoding v5 related tests

[underoot]

We shouldn't rely on the external API (relative to the library itself) for testing. While I fixed the currently failing test in the main by stubbing, some other test cases rely on the API. Failing tests relying on quite unpredictable behaviour, such as an empty response for a random string, and so on. For now, I suggest fixing these tests by stubbing (or, for fuzzyMatch, by updating the query). Later, we can replace all API-related test cases with stubs.

• briefly describe the changes in this PR
• write tests for all new functionality
• run npm run docs and commit changes to API.md
• update CHANGELOG.md with changes under main heading before merging