add cohort year in dim_student

[keenzarate213]

Description & motivation

Adding cohortYear in dim_student. This is from a collection (relevant staging PR that flattens this).

Relevant Monday item

PR Merge Priority:

• Low
• Medium
• High

Changes to existing files:

• dim_student: just adding cohort year build model and joining it
  

  edu_wh/models/core_warehouse/dim_student.sql

  Lines 220 to 222 in 08f6872

  	left join stu_cohort_year
  	on stu_demos.k_student = stu_cohort_year.k_student
  	and stg_student.api_year = stu_cohort_year.school_year

New files created:

• bld_ef3__student_cohort_years: to bring back to k_student grain after flattening the collection

Tests and QC done:

This branch has been tested in Boston and SC-district warehouse.

Future ToDos

No other collection in stuEdOrg needed to be flatten, there were other fields but non of them are populated in either Boston or SC yet. But in the future, could add those in as well

[rlittle08]

@keenzarate213 can you add a quick col description to dim_student.yaml for the new column?

[rlittle08]

How can we also incorporate cohortYears:schoolYear and cohortYears:Term into the warehouse? Maybe just keep as a variant object in dim_student for now?