Common Genbank `Feature.Type` values should be enumerated

[carreter]

While reviewing @cachemoi 's #350 , I noticed they added an explicit check for the type of a genbank Feature when determining whether the given feature was a coding sequence (feature.Type == "CDS").

Perhaps it would be helpful to encode common feature types into an enum (type FeatureType string) in the genbank package.

Blocked by #339 .

EDIT: another test

[carreter]

Testing to see if the new "blocked by" between issues works:

Blocked by #339 .

[github-actions[bot]]

Status: Ready to merge :heavy_check_mark:

Issues blocking this PR:

• 339 :heavy_check_mark:

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[github-actions[bot]]

This issue has had no activity in the past 2 months. Marking as stale.

[github-actions[bot]]

This issue has had no activity in the past 2 months. Marking as stale.