bug: post_operations unable to see variable declared in per_operations

[ashish10alex]

Describe the bug
Variable declared in pre_operations is not visible in post_operations

To Reproduce
Steps to reproduce the behavior:

config {
  type: "table",
}

pre_operations {
    DECLARE DATE_RANGE INT64 DEFAULT 356 * 3;
}

SELECT 2

post_operations {
    SELECT DATE_RANGE
}

Expected behavior
A clear and concise description of what you expected to happen.

Variable should be visible and no diagnostics should be placed on sqlx file

Screenshots
If applicable, add screenshots to help explain your problem.

Environment:

• Operating system Mac OS
• Dataform cli version v0.3.26
• Dataform core version v0.3.24
• Version of the extension v0.15.0