Create an overload for com.snowflake.snowpark.functions.sum

[sfc-gh-aherreraaguilar]

Please answer these questions before submitting your pull requests. Thanks!

1. What GitHub issue is this PR addressing? Make sure that there is an accompanying issue to your PR.

   Fixes # SCT-2665

2. Fill out the following pre-review checklist:

   • [X] I am adding a new automated test(s) to verify correctness of my new code
   • [ ] I am adding new logging messages
   • [ ] I am adding a new telemetry message
   • [ ] I am adding new credentials
   • [ ] I am adding a new dependency

3. Please describe how your code solves the related issue.

   Added an overload for the sum function which supports a string parameter.

Pre-review checklist

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• [x] This change has passed precommit
• [ ] I have reviewed code coverage report for my PR in (Sonarqube)

[sfc-gh-aherreraaguilar]

@sfc-gh-bli Thanks, I fixed all the comments, please review again.