Fix specs relating to OpencBot::ManualIncrementer

This gets the current specs passing but it probably could do with further scrutiny as to which other tests it needs
Fix bug where `rake bot:test` would update the _last_exported_at field unnecessarily
Change unique_fields check against db to ensure schema matches LicenceRecord

Sqlite’s insert_or_update method is problematic when the unique indexes in the schema change unexpectedly. If a requirement for a unique index is added at the point of database creation but then later removed by the developer, this can lead to a situation where records are duplicated instead of updated in place. Combined with the Enumerator aspects of the bot, this can lead to dangerous loops when exporting the data.

This patch ensures that the unique_fields method matches the unique indexes in the db schema on every run.
Finish consolidating database queries into one place for Simple Bot

The current thinking behind this is to offer potential for a “default_scope” over a bot’s database. In some cases we might be collecting a mix of record types but only want to test and export the Finance related records for example. This commit simplifies the number of ways the database is queried to run via all_stored_records for now
Tidy up simple bot create script
Respect .gitkeep in otherwise ignored folders
Add pry to Gemfile