Adapt parse test for Snowflake edge case

[radeusgd]

Pull Request Description

Fixing a regression in Snowflake tests.

• In Snowflake, the Integer type is superseded by Decimal.
• Thus, a parse test that was checking that parsing a column that already has the right type is na no-op was failing, because on Snowflake the column did not have the 'right type' - we were asking for Integer, but on Snowflake the column had Decimal.
• To fix this, we change the test to ask exactly for the type that the column has:
  • On most backends this will still ask for Integer.
  • On Snowflake this will ask for Decimal and ensure the conversion is still a no-op.
• Due to Snowflake's differences, parse Integer won't work as easily as on other platforms, the user has to ask for Decimal.

Important Notes

Checklist

Please ensure that the following checklist has been satisfied before submitting the PR:

• The documentation has been updated, if necessary.
• Screenshots/screencasts have been attached, if there are any visual changes. For interactive or animated visual changes, a screencast is preferred.
• All code follows the
  Scala,
  Java,
  TypeScript,
  and
  Rust
  style guides. In case you are using a language not listed above, follow the Rust style guide.
• Unit tests have been written where possible.
• If meaningful changes were made to logic or tests affecting Enso Cloud integration in the libraries,
  or the Snowflake database integration, a run of the Extra Tests has been scheduled.
  • If applicable, it is suggested to paste a link to a successful run of the Extra Tests.

[radeusgd]

Extra Tests:

• ❌ https://github.com/enso-org/enso/actions/runs/12868170967
• ✅ https://github.com/enso-org/enso/actions/runs/12869086746