Some improvements to the UpdateClinicalTrials job

[coveralls]

Pull Request Test Coverage Report for Build 561603714

• 0 of 8 (0.0%) changed or added relevant lines in 1 file are covered.
• 34 unchanged lines in 22 files lost coverage.
• Overall coverage decreased (-0.02%) to 15.991%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
app/jobs/update_clinical_trials.rb	0	8	0.0%
<!--	Total:	0	8	0.0%	-->

Files with Coverage Reduction	New Missed Lines	%
app/controllers/genes_controller.rb	1	83.54%
app/models/comment.rb	1	63.64%
app/models/concerns/moderated.rb	1	74.24%
app/models/concerns/with_countable_enum.rb	1	90.0%
app/models/disease.rb	1	69.23%
app/models/drug.rb	1	56.25%
app/models/evidence_item.rb	1	81.63%
app/models/gene.rb	1	84.21%
app/models/notification.rb	1	62.5%
app/models/on_site_subscription.rb	1	40.0%
<!--	Total:	34		-->

Totals
Change from base Build 558880154:	-0.02%
Covered Lines:	2133
Relevant Lines:	13339

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💛 - Coveralls