Added specific months and days to clarify GitLab's fiscal year

Why is this change being made?

Added specific months and days to clarify GitLab's fiscal year

• Q1: February 1 through April 30
• Q2: May 1 through July 31
• Q3: August 1 through October 31
• Q4: November 1 through January 31

Does this MR meet the acceptance criteria?

Yes

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what