feat: toogle for incremental/non-incremental query execution

[ashish10alex]

Solves: https://github.com/ashish10alex/vscode-dataform-tools/issues/39

• [x] Use able to choose on weather to run incremental / non-incremental query to run for previewing results by clicking on checkbox
• [x] Default is set as non-incremental as during the initial development the table would not yet exists for incremental logic to work
• [x] Checkbox only appears if the active file is of type incremental