Add Quality and UX Gearing Ratio PIs

Why is this change being made?

Adds Performance Indicators for UX and Quality Gearing Ratios to close https://gitlab.com/gitlab-data/analytics/-/issues/5908.

Chart	DRI	Gearing Ratio
Software Engineering in Test Gearing Ratio	@meks	One Software Engineer in Test for each product group
Quality Engineering Manager Gearing Ratio	@meks	One Quality Engineering Manager for each product section
Engineering Productivity Gearing Ratio	@meks	One Engineering Productivity Engineer for each product stage
Product Designer Gearing Ratio	@vkarnes	One Product Designer for every stage group
Technical Writer Gearing Ratio	@susantacker	One Technical Writer for three stage groups
UX Researcher Gearing Ratio	@asmolinski2	One UX Researcher for 5 stage groups

Notes

• Data is available from 2020-08 when stages.yml began import with https://gitlab.com/gitlab-data/analytics/-/issues/5976
• The gearing ratio is calculated based on the data in stages.yml and BambooHR as of the last day of the month or the current day for the current month.

Author Checklist

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