SNOW-559970: Add error cast check for SnowflakeError

[satishbhor]

checkQueryStatus API not always returns SnowflakeError, e.g. if context is cancelled by client then it may return *errors.errorString, Hence we should have check whether its SnowflakeError or not, otherwise it will panic and will crash app.

Checklist

• Code compiles correctly
• Run make fmt to fix inconsistent formats
• Run make lint to get lint errors and fix all of them
• Created tests which fail without the change (if possible)
• All tests passing
• Extended the README / documentation, if necessary

[satishbhor]

Hello Team,
Any update on this?

[sfc-gh-dszmolka]

#771

[sfc-gh-pfus]

Hello @satishbhor ! Thanks for your input, this is very valuable. Can you rebase and solve conflicts?

[sfc-gh-pfus]

I noticed, that the only place in which we use casting to snowflakeError was already fixed (as @sfc-gh-dszmolka kindly suggested). So I think that we don't need a dedicated function for casting to snowflakeError.
In that case I'm going to close this PR, but personally I'm always happy if community suggests improvements. Thank you very much! I hope, that in some time you will provide another improvement or a bug fix!