Commit changing each run will regenerate record each time

[jess-lowe]

In #4422 and #4389 we introduced the commit hash link of the record we converted from the CVEList. This will be useful in the future so we're only generating records that have changed, but will mean the hash for upload changes each time we run the conversion.

For the time being, we'll point to the tree/main/ instead of the exact commit.

[github-actions]

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