Exclude 0-level priority assertions in the collection form

[howard-e]

Preview Tests

See #1008.

To test this change:

• Run npm run make-v2 <pattern>
• Update any of the created *-commands.csv's row value for the "assertionExceptions" column with 0:<assertionId> ...
  • Note: assertionId must match a defined assertionId of a row in the generated assertions.csv
  • Note: tests.csv must include the assertion id in a row's "assertions" column
• Run npm run build
• Observe that the assertion is excluded on <baseurl>/review/<pattern>.html under the expected command (this was included before this PR)
• Select an AT link under tests and observe that the assertion is excluded on <baseurl>/tests/<pattern>/<testfile_name>.html under the expected command

Note that #1014 has also been submitted to make previewing those changes easier (check description for changes and preview link)

[alflennik]

I was able to verify that excluded assertions do not appear. Code looks good.

[stalgiag]

Tested and I was able to exclude assertions. I didn't notice any issues with the code.