Ensure db:seed runs before spree_sample:load

[lsizani]

Summary

When running bundle exec rake spree_sample:load against an empty database, an exception is raised in db/samples/tax_rates.rb on account of missing a Spree::Zone with the name "North America.

In this PR we:

• Add db:seed as a dependent task of spree_sample:load
• Check that Spree::Zone "North America" is present in db/samples/tax_rates.rb before running the rest of the seed file. This makes it consistent with db/samples/shipping_methods.rb

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[lsizani]

Thanks! I left a comment. Also, I'm curious about what happens if db:seed and sample:load are run independently, one after the other. Is db:seed executed twice in that case?

It will run db:seed twice in that case. I checked on this and I can confirm that the current seeds can be run multiple times without raising errors or duplicating data.

[kennyadsl]

@lsizani do you know if we have any spec that verify we can run seeds multiple times without breaking or creating duplicate records?

[lsizani]

@lsizani do you know if we have any spec that verify we can run seeds multiple times without breaking or creating duplicate records?

We do not... But I'm sure I can write one

[kennyadsl]

Hey @lsizani! I lost track of this PR, I didn't notice you updated it following my suggestions. I will re-review it now, in the meantime there are some conflict with the main branch to address, if you have time for a rebase. Thanks again!