Add actions tests

[mariorodeghiero]

Create tests to cover the actions resource_sample_show and resource_schema_show after the PR https://github.com/datopian/ckanext-blob-storage/pull/30

Acceptance

• [x] Add test for resource_sample_show
• [x] Add test for resource_schema_show

Tasks

• [x] Create new actions_test file
• [x] Add test for resource_sample_show
• [x] Add test for resource_schema_show

cc: @shevron

[mariorodeghiero]

Update:

• I pushed this PR for your review with the tests https://github.com/datopian/ckanext-blob-storage/pull/34