Snowpark Project definition: support marking UDFs as "STRICT" and "IMMUTABLE"

[gwerbin-tive]

Description

It would be useful if we could specify these options in the Snowpark YAML project definition. These options are already supported in the Snowpark Python API.

Hypothetical example:

entities:

  hello_function:
    type: function
    identifier:
      name: hello_function
    handler: functions.hello_function
    signature:
      - name: name
        type: string
    returns: string
    strict: true
    immutable: true
    meta:
      use_mixins:
        - snowpark_shared

Context

RETURNS NULL ON NULL INPUT / STRICT makes UDF handler development easier by allowing the author to ignore null inputs. IMMUTABLE can be important for optimization in certain situations.

[gwerbin-tive]

I started a patch for this, not sure when I'll have time to work on it more though: https://github.com/gwerbin-tive/snowflake-cli/compare/351f5dd488d2d9e5bda1ce72eecc18b424b52901..5decd010989852e9c12919eb4bce15b79ea6f229