SNOW-922989 Replace deprecated bignumber.js floor function

[mblakley]

Description

Replaced the deprecated floor function in new versions of bignumber.js (>= 6.0) with the updated solution of calling .integerValue(BigNumber.ROUND_FLOOR)

Checklist

• Format code according to the existing code style (run npm run lint:check -- CHANGED_FILES and fix problems in changed code) - I ran this, and there are a lot of warnings in the existing column.js file.
• Create tests which fail without the change (if possible)
• Make all tests (unit and integration) pass (npm run test:unit and npm run test:integration) - Ran unit tests, no new failures
• Extend the README / documentation and ensure is properly displayed (if necessary)
• Provide JIRA issue id (if possible) or GitHub issue id in commit message

[github-actions]

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[mblakley]

I have read the CLA Document and I hereby sign the CLA

[mblakley]

Thank you for reviewing! Another possible solution would be to set an upper bound on the bignumber.js version in package.json - my initial thought was that my proposed solution would allow moving to the newest versions of that package instead of sticking with the older versions.

[sfc-gh-pbulawa]

Hi @mblakley,

Thanks for your contribution! I have ran your branch in #656 and it seems that the newer version of the bignumber.js is having different API:

Uncaught TypeError: valFracSecsWithTzBig.greaterThanOrEqualTo is not a function
      at Object.convertRawTimestampTz [as convert] (/mnt/host/lib/connection/result/column.js:462:30)

Could you please take a look into it and update the code?

[mblakley]

I made updates to my branch.

Luckily, the API name updates for greaterThanOrEqualTo were also done in v6.0 of the bignumber.js package, so there's no conflict with using that version as the minimum.

[sfc-gh-pmotacki]

@mblakley thank you for your contribution.