set up a cron to build the action's javascript

[devoncarew]

• set up a cron to build the action's javascript

We have weekly cron's to test the action but not to verify that we can build the action's javascript (from the latest dev sdk). This adds a cron for the build workflow (it'll help us catch things like #95 sooner).

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[devoncarew]

(note that this PR is expected to fail - I'll address the analysis issues in a follow-up PR)